Vol. 6; Supplement Page 71 THE VELIGER Distribution and Utilization of Gastropod Shells by the Hermit Crabs Pagurus samuelis. Pagurus granosimanus, and Pagurus hirsutiusculus at Pacific Grove, California MELODY BOLLAY Hopkins Marine Station of Stanford University, Pacific Grove, California (6 Text figures; 1 Table) SEVERAL SPECIES OF Pagurus occur in the rocky intertidal cheliped very dark brown contrasting with the lighter zone at Pacific Grove, California. The majority of the brown of the rest of the leg. In general, both P samuelis larger hermit crabs are found in shells of Tegula funebralis and P granosimanus are relatively large, reaching an (A. ADAMS, 1854), this being the only snail in the area overall extended length of 6 and 7 cm, respectively, where- which is both large enough and abundant enough to as P hirsutiusculus is a smaller species, not frequently supply the larger pagurids with homes. It therefore ap exceeding 4 cm in length. pears that the T funebralis population might be one of To study the distribution problem, transects were the factors limiting the hermit crab population. In in¬ taken running seaward from the shore in three different quiring into the relationship between snail and crab areas: tried to determine the following: (1 What species of Area A. Rocky exposed coast, rich in algal growth. Pagurus are present, how are these distributed, what Area B. Large granite outcrop with rough surf and surge, factors influence this distribution? (2) What shells are barnacles and mussels predominate. used by the different species and how does this correlate Area C. Semi-protected rocky area, rich in algal growth. with the size and distribution of the T. funebralis popu- (see WARA, W., & B. WRIGHT, 1964, for detailed lation? descriptions and profiles of these areas.) The hermit crabs collected intertidally at the Hopkins In each transect, samples were collected at two meter Marine Station, Pacific Grove were identified using the intervals, starting at the shore. The first 100 hermit crabs descriptions in SCHMITT (1921). The following species seen at each site were taken, or as many as could be were found: Pagurus samuelis (STIMPSON, 1857), P found if 100 were not present. Collecting was not done granosimanus (STIMPSON, 1859), and P hirsutiusculus at low tide, since at that time the hermit crabs are most (DANA, 1857). Of the 1873 hermit crabs collected, 50% difficult to find, being hidden under rocks and in crevices. were P samuelis, 40% P hirsutiusculus, and only 10% The hours immediately preceding or following a low were P granosimanus. Samples included both young and tide are better, when water covers most areas yet is adult specimens from each species. The young were identi- shallow enough to allow collecting. Results are shown fied by using a series of animals of graded size for each in Figures 1 and 2. species, and noting color patterns on both antennae and Of the three species, Pagurus samuelis was the only body. Identifying characteristics for the younger hermit one found at the highest levels in the intertidal, while crabs are as follows: P samuelis - red antennae and either both P granosimanus and P hirsutiusculus occupied lower white or blue bands on the walking legs; P granosimanus regions, areas usually covered by water. In area C, the like adult in color; P hirsutiusculus - dark olive-green P samuelis represent the only hermit crabs found both antennae striped with white, ambulatory legs striped with close to shore and at the outer part of the transect white (never with blue), merus on both large and small because of a large rock outcropping at the outer margin. Vol. 6; Supplement Page 72 THE VELIGER 100 87 100 100 94 4 47 97 84 100 XX 00 Pagurus samuelis —X— 40 Pagurus hirsutiusculus Pagurus granosimanus — Profile of Area A ML — Sea Distance from shore (Meters) Shore Figure 1: Relative Abundance of Three Pagurus Species in Area A Collecting was done on two consecutive days, May 8 and 9, 1963, the first sunny and the second overcast, from 6:15 a. m. to 10:00 a. m. and from 7:00 a. m. to 10:30 a. m. respectively. This was from the low tide until it became too rough to collect. No sample size The P hirsutiusculus and the P granosimanus are again Pagurus samuelis was found up to a height of about concentrated in the deeper lying regions, which this 4 feet but in far fewer numbers, sample sizes at each collecting station averaging 10.1 for this transect as a time are in the center of the transect. As shown by the whole. Of the 97 Pagurus collected, only 44.3% were P sample size (N) there were far fewer hermit crabs at the higher sites along the transect, all that were found samuelis, 55.7% were P hirsutiusculus. Since the differences in distribution might reflect dif¬ being taken, whereas in the lower areas there was no difficulty in finding 100 for the sample. ferences in ability to withstand the effects of exposure, an experiment was conducted to see if there was any differ- What can be seen intuitively in these first two graphs that the three species are probably distributed dif¬ ence in the survival between the three species when ferentially with respect to height — is clearly illustrated exposed out of water in daylight. The bottoms of three plastic dishpans were covered with dry sand. Each pan in Figure 3, in which the data from areas A and C are received 30 hermit crabs of one species. The Pagurus combined and species distribution is plotted against verti¬ cal position in the intertidal. Above 1.2 m only Pagurus samuelis and P granosimanus used were all large adult samuelis is found, while this species represents over 50% specimens. The P hirsutiusculus, while adults, were of all the hermit crabs found at 0.6 m. With increasing necessarily smaller. The data are shown in Figure 4. depth the proportion of P samuelis declines while that of From this test it appears that P hirsutiusculus and P both P granosimanus and P hirsutiusculus increases. granosimanus are less able to survive exposure than P samuelis; the smaller individuals died sooner on exposure The data from area B (not shown) confirm these findings, but in this transect Pagurus granosimanus was out of water than the larger ones. Although more ex- entirely absent; however, P hirsutiusculus was found at periments would be desirable, these results suggest that the lowest extremity of this steep transect and in approxi¬ differences in the ability to withstand exposure help to matcly the same numbers as in the other two areas. explain the differences in distribution of the three species. Page 73 Vol. 6; Supplement THE VELIGER 106 6 96 2 32 24 0 4 — 109 93 103 109 2 — — X 00 Pagurus samuelis 60 40 Pagurus hirsutiusculus Pagurus 20 granosimanu Profile of Area C O MLLN 13 15 17 8 20 22 24 26 28 30 Sea Distance from shore (Meters) Shore Figure 2 Collecting was done on two consecutive days, May 16 and 17, 1963, both cloudy, from 9:00 a. m. to 12:10 p. m. and from 9:30 a. m. to 12:30 p. m., respectively. This was from a period just preceding low tide up until low tide. N = sample size; (—) = no sample taken noted previously that the smaller P samuelis seemed less Ne 295 - 100 493 497 - 92 able to survive exposure. That the smaller specimens seem o0- also to live higher in the intertidal is not necessarily a Nagurus samuelis contradiction because the small hermit crabs (1) are not found exposed, but rather stay under rocks, etc., and 80 (2) are more readily able to find such protection than the larger Pagurus which stay in areas where they are 60 usually submerged. Pagurus In the field it was noted that the majority of the larger hirsutiusculus hermit crabs occupied Tegula funebralis shells. Figure 5 Pagurus granosimanus compares the use made of various shells by the three to species. It would appear that both Pagurus granosimanus and P samuelis are extremely dependent on T. funebralis - - for homes, since 89% and 76%, respectively, are found in these shells. REESE (1962) reports that larger P granosi- manus in southern California were usually found in large Height in meters Tegula shells, and suggests this was because, of the shells available, only those of Tégula were large enough to Figure 3: Relative Abundance of Pagurus Species at accommodate the larger crabs. Of all the P hirsutiusculus, Different Elevations, Areas A and C. however, only 10.9% occupy T funebralis shells. This -) — no sample taken N = sample size; latter species is much more dependent on a number of smaller snails including Littorina spp., Calliostoma spp., Of the commonest pagurid, Pagurus samuelis, the Epitonium spp., Mitrella spp., Homalopoma spp., etc. In smaller individuals generally live higher up in the inter- area B, however, the situation is interestingly different. tidal, the largest members only deeper down. It was Page 74 Vol. 6; Supplement THE VELIGER collected from the three transects, 73.9% were inhabited laate —XX— by Pagurus samuelis, 17.5% by P granosimanus, and 8.5% by P hirsutiusculus. It is quite obvious that most of the 7. funebralis shells are used by the two larger species of hermit crabs while the smaller shells (“other") are 94.6% 20 occupied by P hirsutiusculus. Pagurus The shells utilized by different sizes of hermit crabs samuelis vary also in size. Although the hermit crabs were not measured directly, they were divided into three classes on the basis of the sizes of the shells occupied. Shell sizes in different species of snails were compared by taking the Pagurus maximum basal diameter of the shells. This gives only Pagurus granosimanus hirsutiusculus an approximate measurement of the size of the shell and OL of the crabs within, because (1) any given shell can be occupied by hermit crabs of a certain range of sizes, and 13:30 14:30 16:30 5:30 (2) shell sizes, as indicated by basal diameter measure¬ Hours exposure and time of day ments, allow only a rough size comparison when applied to shells of different species of snails. Nevertheless, the shell measurements indicate the size of the pagurid inside Figure 4: Survival of Pagurus Species on Exposure well enough to allow us to separate the crabs into large, to Air and Sunlight medium, and small size groups. Data on species of snail shells occupied by pagurids of different size ranges are Of the P hirsutiusculus found, none were in T funebralis shown in Table 1. Obviously, the larger the hermit crabs shells, while much greater use was made of Littorina and grow, the more dependent they become on the Tégula Thais shells than in the other two areas. funebralis population for homes. Figure 6 shows the relative utilization, by the three This raises the interesting question: do Pagurus grano¬ species of hermit crabs, of various shells which are simanus and P samuelis achieve sexual maturity before common in the locality. For instance, of all the Tegula they reach a size too large to fit into any shells but those funebralis shells occupied by hermit crabs which were Pagurus samuelis ta- N -189 Pagurus granosimanus N - 75 Pagurus hirsutiusculus ..... 40% 50% 60% 70% 80% 90% 0% 10% 20% 30% Tegula funebralis Acanthina spirata &am NTegula brunned Thais emarginata Littorina spp. Other species: Colliostoma spp, Epitonium spp, Mitrella spp, Homalopoma spp, etc. N = Sample size Figure 5: Comparison of Shells Occupied by Three Species of Pagurus Page 75 Vol. 6; Supplement THE VELIGER area. The P samuelis here make much greater use of of Tegula funebralis, locally? Information could not be Thais and Littorina shells — these snails being found in obtained on P granosimanus, but for P samuelis specimens much greater abundance here than in the other areas. as small as 1.1 cm total extended length have been Perhaps, then, the two larger species of Pagurus are collected bearing eggs. Animals this size are not heavily limited by the lack of suitable shells even though a few dependent on T funebralis (see Table 1) since they can P samuelis were found here. It is possible that the reason easily fit into shells less than 1.0 cm in greatest basal no P granosimanus were found in this area was that they diameter. Since sexual maturity is, in P samuelis, attained do not reach sexual maturity until they have attained relatively early, this species (like P hirsutiusculus) is a much larger size; however, this was not determined. probably able to survive and reproduce in areas where shells suitable to house larger individuals are not avail¬ Table 1 able. However, the number of eggs borne by the smaller sizes of P samuelis is very much less than the number Greatest Basal Shell Diameter produced by a fully grown specimen. Therefore, repro¬ §1.0 cm 1.0 to 2.0 cm 2.0 to 3.0 cm ductive potential in the absence of large (e. g. T. funeb- N =488 N = 289 N = 107 Tegula ralis) shells would be lower. % = 15.6 % = 94.4 % = 83.7 funebralis Area B, as cited already, differed from the other two N= N = Tegula transects. Insufficient food could explain its small popu¬ % = % = 5.3 brunnea %0 = lation. Another possible factor, however, might be the N= N = N= Thais spp. lack of available shells for use as homes. The Tegula % = 0.3 % = % = funebralis population in this area is relatively small (see N= Acanthina spp. N = N= WARA, W, & B. WRIGHT, 1964). The number of Pagurus % - % = 0 % = 0.7 hirsutiusculus is not noticeably less — and this is the one N = N =202 N= Littorina spp. species of the three that does not rely heavily on T. % = 29 % =0 %0 = funebralis shells for homes. On the other hand, there are N = 330 N = 15 N= Other species relatively few P samuelis and no P granosimanus in this 90 — 0 % =47.4 % = 2.5 N- 99 267 E Pagurus hirsutiusculus Pagurus granosimanus S Pagurus samuelis Figure 6: Utilization of Shells by Pagurus in Areas A, B, and C. Page 76 THE VELIGER Vol. 6; Supplement SUMMARY 5. Both Pagurus samuelis and P hirsutiusculus attain sexual maturity at a relatively small size and thus are not 1. Of the three species of hermit crabs found in the completely dependent on Tegula funebralis for the sur- intertidal zone at Hopkins Marine Station, Pacific Grove. vival and reproduction of the species. However, when Pagurus samuelis is the only one encountered at positions larger shells are not available the reproduction potential higher than about 1.2 m, P hirsutiusculus and P granosi- in P samuelis may be greatly reduced since the smaller manus being found lower. individuals produce far fewer eggs than the larger ones. 2. Of the three species, Pagurus samuelis appears to be able to survive exposure out of water better than the other LITERATURE CITED two. Adults of P hirsutiusculus are least able to withstand exposure to air in sunlight. REESE, ERNST 3. The three species make use of various shells to different 1962. Shell selection behavior of hermit crabs. Animal degrees. Eighty-nine % of the Pagurus granosimanus and Behaviour 10: 347 -360 75.9% of the P samuelis collected occupied Tegula funeb- SCHMITT, WALDO L. ralis shells, whereas, the smaller P hirsutiusculus tended 1921. Marine decapods of California. Univ. Calif. Publ. to occupy shells of smaller snails such as Epitonium, Zool. 23: 1 - 470; plts. 1 - 50; 165 text figs. Mitrella, Homalopoma, etc., to a greater degree. WARA, WILLIAM M., & BENJAMIN B. WRIGHT 4. The bigger pagurid individuals are largely dependent 1964. The distribution and movement of Tegula funebralis in on Tegula funebralis for homes whereas the smaller sized the intertidal region, Monterey Bay, California (Mollusca: Gastropoda). The Veliger 6; Supplement: 30 - 37; 9 text figs. hermit crabs are not, and occupy a variety of small shells. Page 77 Vol. 6; Supplement THE VELIGER Studies on Mollusk Populations VI. — Tegula funebralis (A. ADAMS, 1855 (Mollusca : Gastropoda) RUDOLF STOHLER Department of Zoology, University of California, Berkeley, California 94720 (5 Text figures) ON pages 316 and 317 of the Proceedings of the Zoological No illustrations were available for the typical species or Society of London for the year 1854 (published on May for the variant until DALL in WILLIAMSON (1892) gave 8, 1855) A. ADAMS described our common intertidal black the first figure of a specimen which is presumed to be the type of CARPENTER's variety (see Figure 1). As the turban as follows: description by CARPENTER (l.c., p. 652) is inadequate for 25. CHLOROSTOMA FUNEBRALE, A. Adams. C. testa turbinata, imperforata, nigra, glabra, longitudinal- iter oblique striata, ad suturas crenulata, anfractibus convexiusculis, ultimo rotundato, basi planiusculo, regione umbilicali valde impressa, callo albo obtecta; columella superne sinuata, antice bituberculata, tu¬ berculo supremo prominente; labro nigro marginato. Hab. California. (Mus. Cuming.) This species is somewhat like C. moestum, Jonas, but the spiral callus surrounding the umbilicus is not prominent as in that species. It is to be stressed that he clearly stated it to be imper¬ forate. CARPENTER (1864) distinguished a variety which Figure 1: Copy of figure 6, plate 21, Proceedings United he named subapertum (pp. 627 and 652) : 6. Chlorostoma States National Museum, volume 15: 21. Chlorostoma funebrale (et var. subapertum. One funebrale A. Adams, variety subapertum Cpr., basal view sp.). of type specimen showing umbilical pit; 30 millimeters, 123496” 77 b. Chlorostoma funebrale, var. subapertum, with umbilical pit. a decision as to what constituted a pit in his view, we must This variety, apparently based on a single shell, may be rely on DALL’s figure to be indeed the type figure; if we assumed to be from the "Vancouver district," specifically assume this to be correct, then an umbilical pit may be from "Neeah Bay, W. T" (CARPENTER, l. c., pp. 626, 627). stated to be a shallow but distinct depression in the What was then the Washington Territory is now the State umbilical area. of Washington. From CARPENTER's account, however, it As indicated previously (STOHLER, 1950), the presence is not entirely clear where exactly the variant shell came or absence of an umbilical opening, pit or depression may from since it was contained in one of many boxes of shells vary greatly in any given population of certain species of received from the ardent collector, Swan, who, moreover. Tégula. Similar results were obtained in a study of popula- "trained the native children to pick up shore-shells in tions of Tégula rugosa (A. ADAMS, 1853) (STOHLER, large quantities." 1963). Vol. 6; Supplement Page 78 THE VELIGER Table 1 Relative Frequency of Deep Umbilical Pits in Populations of Tegula funebralis from the Eastern Pacific Baja California (Mexico) Santa Cruz County Santa Cruz Punta Banda Scott Creek La Mision Rio Guadalupe San Mateo County Punta Mesquite Pigeon Point Punta Piedra Pillar Point Rosarito Beach Frenchman's Reef Moss Beach California Marin County San Diego County Duxbury Reef Point Loma Drakes Estero Flood Control Channel Tomales Point La Jolla Sonoma County Orange County Bodega Dana Point Carmet by the Sea Los Angeles County Shell Beach Point Fermin Russian Gulch I White’s Point Salt Point Ventura County Horseshoe Point Stewarts Point San Nicolas Island Rincon Beach Del Mar Point Santa Barbara County Mendocino County Santa Rosa Island Havens Neck Arena Cove San Miguel Island Gaviota Government Point Fort Bragg Hardy San Luis Obispo County Humboldt County Morro Bay Cayucos S. of Cape Mendocino Moonstone Beach Del Norte County San Simeon 1 mi S. of Oregon Border Montercy County at Oregon Border Soberanes Point Yankee Point Subtotal: Point Lobos Point Buchon Mission Point Cannada Tecelate Spanish Bay Total: 285 28 Monterey Harbor 465 596 Page 79 Vol. 6; Supplement THE VELIGER In the collection of the Department of Zoology of the Table 3 University of California in Berkeley there is a number of Population of Tegula funebralis from West of Canada small lots of Tegula funebralis from the shore of the Tecelate, Santa Rosa Island, Santa Barbara County Eastern Pacific extending from Lower California to the (Measurements in millimeters) northern border of California. A total of 596 shells was examined for the presence or absence of an umbilical pit. flat shallow deep This examination revealed that T. funebralis is indeed im 36.1 41.2 35.5 height perforate exactly as ADAMS stated, for not a single speci¬ largest 30.7 width 31.4 31.0 men in the 55 lots studied had an open umbilicus 173 height 11.2 11.0 However, it was also noted that a deep umbilical pit smallest 20.8 width 11.8 13.4 could be observed in many lots regardless of the place of origin (see Table 1) ; this was true for 13 of the 55 lots examined; a shallower pit was seen in 47 of the 55 lots, collection, having a deep umbilical pit, is from Rio all of the previously mentioned 13 lots also containing such Guadalupe, Baja California, Mexico, and measures 17.0 specimens. On the other hand, only 7 of these lots showed mm in diameter. It is perhaps worth noting that the pro- a complete absence of specimens with an entirely flat portion of shells with a deep umbilical pit to the total umbilical area. population is fairly constant, i.e. 4%, while "flat" and It is my impression that had larger samples been taken "shallow" vary from approximately 85:10 (at Point in all localities the three types of umbilical areas (i. e Buchon) to 52:42 (at Canada Tecelate). The percentage deep pit, shallow pit, and smooth area) would have been of shells with the deep pit seems to remain fairly constant found to be more evenly distributed. Unfortunately, at the in all populations, that is if we may make this deduction time these collections were made the problem of the based on the two larger samples just discussed, either umbilical area was not considered and usually only very separately or together, or basing the assumption on the small samples were retained as indicators of the presence total figures of all samples studied. of Tegula funebralis in a particular locality. Through the Two other observations were made during this partic- generous cooperation of Mr. Glen Bickford from the ular study. The first one is that the sculpture of the whorls California Department of Fish and Game I have been is fairly constant throughout the range of distribution of able to examine two larger lots, one from the mainland the species; the "aureotincta" sculpture, as discussed in shore in San Luis Obispo County and one from Santa connection with Tegula brunnea (PHILIPPI, 1848) (STOH- Rosa Island. These two lots I considered large enough for LER, 1958) and T rugosa (STOHLER, 1963) has not been taking some measurements (see Tables 2 and 3). Measure- seen in any specimen; not even the faintest indication of such a sculpture has been noticed, although I paid special Table 2 attention to this feature of the shell. Population of Tegula funebralis from about ½ mile North of Point Buchon, San Luis Obispo County (Measurements in millimeters) flat shallow deep height 31.4 26.5 25.9 largest width 31.7 27.4 4.5 height 12.9 21.5 smallest width 6.1 15.4 23.5 ments of height in T funebralis cannot be considered significant, generally speaking, because of the varying degrees of corrosion. More reliance may be put on the largest diameter of the shell. Scanning Tables 2 and 3 one must gain the impression Figure 2: Tegula funebralis (A. ADAMS, 1855). that a deep umbilical pit is limited to large (that is, older) Duxbury Point, Marin County, California. Oct. 30, 1947. shells. But studying the smaller lots in the collection this Lateral aspect. ex Coll. Dept. Zool., Univ. Calif., Berkeley. impression is dissipated. The smallest specimen in the (X 1) Page 80 Vol. 6; Supplement THE VELIGER ecological conditions similar to those at Duxbury Reef The second observation is, however, of a more positive nature. At Duxbury Reef in Marin County a large pro- seem to prevail. On the other hand, in general collections of Tegula funebralis, covering wide ranges of its distri- portion of the Tegula funebralis shells encountered are bution, such as are housed in the California Academy of Sciences in San Francisco, these large, high specimens can be readily picked out; when the museum label is examined it is found to read "Baulinas," "Bolinas" or "Duxbury. all three being, to some collector or other, the same spot. Figure 3: Same shell as shown in Figure 2. Ventral aspect. ex Coll. Dept. Zool., Univ. Calif., Berkeley. (X 1) unusually high (Figures 2, 3) ; rough estimates made in the field vary slightly, depending on certain closely cir- Figure 5: Same shell as shown in Figure 4. cumscribed areas scrutinized. In the sandy areas, devoid Ventral aspect. ex Coll. Dept. Zool., Univ. Calif., Berkeley. of all rocks, no T funebralis are encountered, except very (X 1) rarely a stray specimen ploughing through the sand on its way from one rocky area to another one. In areas with For the same reason as given in our previous papers, small rocks up to the size of a large fist, Tegulas abound cited above, we do not consider the variety subapertum to be taxonomically valid; it is merely a variant, perhaps and here the proportion of the high forms is estimated at the end of the range of variability for the particular at about 40% of the total number; these rocky areas are bounded by large rocks forming actual reefs; Tegulas character, but still one that is difficult to define exactly since what is a “depression" in the umbilical area must inhabiting this particular environment seem to comprise a remain open to a very subjective appraisal by the observer. larger percentage of high shells, probably as many as On the other hand, a decision whether the Duxbury 75% or even more being of the type shown in Figure 2. variant should be considered a taxonomically valid sub¬ The other members of these various Tegula populations species must be deferred, I think, until breeding experi¬ conform to the more usual shape pattern (see Figures 2 ments can be conducted to ascertain whether this is a and 5). heritable character, unaffected by environmental factors, It seems plausible that these high forms represent an or a character influenced only by some as yet unrecognized ecological variant, although I have not seen similar shells in any other collecting station along the coast of California environmental condition. and Lower California, even though in one or two places ACKNOWLEDGMENTS The illustrations reproduced here are the product of the fine artistic skill of Mrs. Emily Reid, Staff Artist in the Department of Zoology. I also wish to express my appreci- ation to Mr. Glen Bickford, not only for his generous donation of the shells discussed here, but also for many other sizable lots and numerous important data, which, it is hoped, will be used in a forthcoming study. LITERATURE CITED Figure 4: Tegula funebralis (A. ADAMS, 1855). ADAMS, ARTHUR Mission Point, Carmel, Monterey County, California. 1855. Descriptions of twenty-seven new species of shells from November 13, 1947. the collection of Hugh Cuming, Esq. Proc. Zool. Soc. Lon¬ Lateral aspect. ex Coll. Dept. Zool., Univ. Calif., Berkeley. don 22: 311 -317 (8 May 1855) (X 1) Vol. 6; Supplement Page 81 THE VELIGER CARPENTER, PHILIP PEARSALL 1864. Supplementary report on the present state of our know- ledge with regard to the Mollusca of the West Coast of North America. Rept. Brit. Assoc. Adv. Sci. for 1863: 517 - 686 DALL, WILLIAM HEALEY in M. BURTON WILLIAMSON 1892. An annotated list of the shells of San Pedro Bay and vicinity with a description of two new species by W. H. Dall. Proc. U. S. Nat. Mus. 15: 179 -220; plts. 19 - 23 STOHLER, RUDOLF 1950. Studies on mollusk populations: I. Tegula gallina Nautilus 64 (2) : 47-51 (October 1950) (FORBES) 1958. Studies on mollusk populations: IIla Tegula brunnea (PHILIPPI) Nautilus 71 (4) : 129 - 131; 1 text fig (April 1958) 1963. Studies on mollusk populations V. — Tegula rugosa (A. ADAMS, 1853) The Veliger 5 (3) : 117 -121; 4 text (1 January 1963) W Vol. 6; Supplement Page 82 THE VELIGER THE CALIFORNIA MALACOZOOLOGIGAL SOCIETY, Inc. Backnumbers of is a non-profit educational corporation (Articles of In¬ THE VELIGER corporation No. 463389 were filed January 6, 1964 in and other publications the office of the Secretary of State). The Society publishes Volumes 1 and 2 are out of print a scientific quarterly, the VELIGER. Donations to the Volume 3: §. 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Even topics only indi- rectly concerned with mollusks may be acceptable. In the unlikely event that space considerations make limitations necessary, papers dealing with mollusks from the Pacific region will be given priority. However, in this case the term "Pacific region" is to be most liberally interpreted. It is the editorial policy to preserve the individualistic writing style of the author; therefore any editorial changes in a manuscript will be sub- mitted to the author for his approval, before going to press. Short articles containing descriptions of new species or lesser taxa will be given preferential treatment in the speed of publication provided that arrangements have been made by the author for depositing the holotype with a recognized public Museum. Museum numbers of the type specimens must be included in the manuscript. Type localities must be defined as accurately as possible, with geographical longitudes and latitudes added. Short original papers, not exceeding 500 words, will be published in the column "NOTES & NEWS"; in this column will also appear notices of meetings of the American Malacological Union, as well as news items which are deemed of interest to our subscribers in general. Articles on "METHODS & TECHNIQUES" will be considered for publication in another column, provided that the information is complete and tech- niques and methods are capable of duplication by anyone carefully fol¬ lowing the description given. Such articles should be mainly original and deal with collecting, preparing, maintaining, studying, photo¬ graphing, etc., of mollusks or other invertebrates. A third column, en- titled"INFORMATION DESK," will contain articles dealing with any problem pertaining to collecting, identifying, etc., in short, problems encountered by our readers. In contrast to other contributions, articles in this column do not necessarily contain new and original materials. Questions to the editor, which can be answered in this column, are in- vited. The column "BOOKS, PERIODICALS, PAMPHLETS" will attempt to bring reviews of new publications to the attention of our readers. Also, new timely articles may be listed by title only, if this is deemed expedient. Manuscripts should be typed in final form on a high grade white paper, 8½2" by 11", double spaced and accompanied by a carbon copy. EDITORIAL BOARD DR. DONALD P ABBOTT, Professor of Biology Hopkins Marine Station of Stanford University DR. J. WYATT DURHAM, Professor of Paleontology University of California, Berkeley DR. E. W. FAGER, Associate Professor of Biology Scripps Institution of Oceanography, University of California, La Jolla (San Diego) DR. CADET HAND, Professor of Zoology and Director, Bodega Marine Laboratory University of California, Berkeley DR. G DALLAS HANNA, Curator, Department of Geology California Academy of Sciences, San Francisco DR. JOEL W. HEDGPETH, Professor of Zoology Director of the Pacific Marine Station Dillon Beach DR. LEO G. HERTLEIN, Curator, Department of Geology California Academy of Sciences, San Francisco DR. MYRA KEEN, Associate Professor of Paleontology and Curator of Conchology Stanford University DR. JOHN MCGOWAN, Assistant Professor of Oceanography Scripps Institution of Oceanography, University of California, La Jolla (San Diego) DR. FRANK PITELKA, Professor of Zoology and Chairman Department of Zoology University of California, Berkeley MR. ALLYN G. SMITH, Associate Curator, Department of Invertebrate Zoology, California Academy of Sciences, San Francisco DR. RALPH I. SMITH, Professor of Zoology University of California, Berkeley DR. DONALD WILSON, Assistant Professor of Zoology University of California, Berkeley EDITOR-IN-CHIEF DR. RUDOLF STOHLER, Associate Research Zoologist University of California, Berkeley ASSOCIATE EDITOR MRS. JEAN M. CATE, Los Angeles, California