LIST OF PLATES. XXXili 



Page. 



254. Sea Snails, Periwinkles, Drills, and Borers 693 



FIG. 1. Lunatia hcros. See Report U.-S. Fisli Commission. Part I, p. 700. 



FIG. '2. Purpura lapillus. See Report U. S. Fish Commission. Parti, p. 698. 



FIG. 3. Purpura lapillus, banded varirty. 



FIG. 4. ytrcritn diiplicata. See Report U. S. Fish Commission. Part I, p. 700. 



FIG. 5. Ityunawa obsohta. See Report U. S. Fish Commission. Parti, p. 696. 



FIG. 6. Ti'ilia tririttata. 



FIG. 7. The Whelk, Jiucciiiiim iniiiatiim. See Report U. S. Fish Commission. Parti, p. 699. 



FIG. 8. The Periwinkle, Fulyer carica. Seo Report U. S. Fish Commission. Part I, p. 694. 



FlG. 9. Anti/ris zonalis. 



FlG. 10. .Ish/n's lunata. 



FlG. 11. Hisxoa aculeatus. 



FIG. 12. The Drill or Borer, UrosaJpinx nnerea, p. 697. 



255. Various species of clams 703 



FlG. 1. Angnliix tcner. 



Aiiiin.il reduced one-half. See Report U. S. Fish Commission. Part I, p. 677. 



FIG. 2. The Long Clam, Soft Clam, or Marminose, Mija arenaria. 



"With animal in extension, reduced to one-half the natural size. 

 FlG. 3. Tai/cliis gibbits. 



With animal, the siphon not fully extended. One-half natural size. See Keport TJ. S. Fish Commission. Part I, p. 675. 

 FIG. 4. The Razor ClamJ Ennatellu amcricana. See Report U. S. Fish Commission. Part I, p. 707. 



"With animal extended. Oue-half natural size. 



FIG. 5. Shows some of the terminal papilla) enlarged. 



FIG. 6. The Razor Clam, Ensatetla americana. 



Shell. Natural size. 

 FIG. 7. The Ship Worm, Teredo vai'aiis. 



Enlarged two diameters. 



FIG. 8. The Scallop, Pecten irradians. See Report U. S. Fish Commission. Part I, p. 709. 



Natural size. 



FIG. 9. The Bloody Clam, Argina pcxata. 

 Natural size. 



256. Various species of clams 703 



FIG. 1. The Quahaug or Little-necked Clam, Venus mercenaria. 



Natural size. 



FIG. 2. The Quahaug of Puget Sound, Saxidomns Nutlalli. 



Natural size of large specimen. Drawn by .T. II. Emerton. 

 FlG. 3. The Gaper Clam of the West Coast, Schizotharus XiiltaUi (Conrad). 



(I.) Specimen of ordinary size, reduced about one-fourth in length. The siphons are somewhat contracted; the foot (F) 



expands about as usual. 

 (II.) Outline of the left valvo of alarger specimen, reduced to the same extent. Drawn from nature by K. E. C. Stearns. 



257. TheGeoduck, or Giant Clarn of the Pacilic, GJi/cimeris generosa 708 



Natural size ; specimens with siphons partly contracted! weight when alive, 6j pounds. Drawn by E. E. C. Stearns. 



258. Mussels and Sea Clams 709 



FIG. 1. The Beach Clam or Hen Clam, Splsula soUdissima. See Report U. S. Fish Commission. Part I, p. 703. 



Natural size. 



FIG. 2. The Sea Clam, Cyprina islandica. 

 Natural size. 



FIG. 3. The Black Mussel, Mi/tilus edulis. See Report U. S. Fish Commission. Part I, p. 709. 

 FlG. 4. The Black Horse Mussel, Modiola nigra. 



FIG. 5. The Roii^h .Mussel, Modiola plicatula. See Report U. S. Fish Commission. Part I, p. 709. 

 FIG. G. Thr Horse Mussel, Modiota modiolu*. See Report U. S. Fish Commission. Part I, p. 709. 



259. The anatomy of the oyster. (See opposite page for full explanation) 711 



260. FIG. 1. The Rock Crab, Cancer irroratus Say ; male one-half natural size 766 



FlG. 2. Zoea of the same, in the last stage before it changes to the megalops condition; lateral view, 



enlarged seventeen diameters. 

 FIG. 3. Megalops stage of the same, just after the change from the zoe'a condition; dorsal view, enlarged 



thirteen diameters. 



FIG. 4. The Jonah Crab, Cancer borcalis Stimpson ; male, two-thirds natural size 769 



FIGS. 5, 6. Terminal joints of the big claws of the same, viewed from the outer side, natural size. 

 Drawings by J. H. Emerton. 



261. The Common Crab of the Pacific Coast, Cancer magister Dana; male, somewhat smaller than natural size. . 770 



Drawing by H. L. Todd, from No. 2553, TJ. S. Nntiou.il Museum. California, William Stimpson. 



