AKT. 17 ILLUSTRATIONS OF TYPES OF SHELLS DALL 37 



Plate 15 



rage 

 Fk!. 1. Acmaea digitalis Eschscholtz, series showing variations, natural 



size, F. W. Kelsey photo 2 



Plate 16 



Fig. 1. Acmaea digitalis Eschscholtz, series continued, natural size, F. W. 



Kelsey photo 2 



Plate 17 



Fig. 1. Corbula macdonaldi T>a\\, Ion. 23 mm 15 



2. Valuta alfaroi Dall, alt. 51 mm 30 



3. Corbula macdonaldi Dall, Ion. 23 mm 15 



4. Marginella macdonaldi Dall, alt. 28 mm 20 



5. Marginella macdonaldi Dall. alt. 28 mm 20 



6. Pecten (Lyropecten) pittieri Dall, alt. 132 mm 23 



7. Area (Scapharca) pittieri Dall, alt. 25 mm 5 



8. Recluzia palmeri Dall, alt. 22.5 mm 25 



9. Area {Noetia) macdonaldi Dall, Ion. 45 mm 5 



Plate 18 



Fig. 1. Semele ruhropicta Dall, interior right valve. Ion. 28 mm 26 



2. Semele ruhropicta Dall, exterior of right valve. Ion. 28 mm 26 



3. Yoldia perprotracta Dall, Ion. 29 mm 32 



4. Gyrinopsis cowlitzi Dall, alt. 65 mm 18 



5. Sthenorytis toroense Dall, alt. 30 mm 27 



6. Gyrinopsis cowlitzi Dall, alt. 65 mm 18 



7. Ischnochiton (Stenoplax) conspicua Carpenter, abnormal six- 



valved specimen, natural size 18 



Plate 19 



Fig. 1. Psammobia (Gobraeus) edentula Gabb, recent specimen. Ion. 



124 mm 23 



2. Yoldia {Cnesterium) excavata Dall, Ion. 30 mm 31 



3. Siliqua patida T>\.xon, Ion. 130 mm 26 



Plate 20 



Fig. 1. Mactra (Mactrotoma) californica Conrad, Ion. 26 mm 19 



2. Anatina (Raetina) indica T)aX[, Ion. 43 ram 2 



3. Serripes laperousii Deshayes, Ion. 110 mm 26 



4. Cuspidaria glacialis Sars, Ion. 37 mm 15 



6. Phacoides {Parvilucina) ienwzscwipio Carpenter, Ion. 12.5 mm 23 



Plate 21 



Fig. 1. Amphissa (Cosmioconcha) parvula Dall, alt. 15.25 mm 2 



2. Suavodrillia sagamiana Dall, alt. 36 mm 27 



3. A ntiplanes yessoensis Dall , alt. 36 mm 4 



4. Neptunea panamensis TiaW, »\i. 22 mm 22 



5. AniipZanes pionffl Dall, alt. 40 mm 4 



6. Afi^ra dolorosa Dall, alt. 19 mm 20 



7. Tromina unicarinata Philippi, alt. 8 mm 28 



