370 CALIFORNIA ACADEMY OF SCIENCES. 



EXPLANATION OF PLATE IV. 



Fig. I. Nassa cerritensis, sp. nov. Upper San Pedro series, Los Cerritos. Type 



specimen. Longitude 31 mm.; Xi.S- 231 



Fig. 2. Volvula cylindrica Carpenter. Lower San Pedro series, Deadman Island. Lon- 

 gitude 7 mm.; X2. 191 

 Fig. 3. Nassa ca/iforttiana CoNRAD. Upper San Pedro series, San Pedro. Longitude 



38 mm.; X3- 231 



Fig. 4. Bitlhim californiawi Dall & Bartsch. Lower San Pedro series, San Pedro. 



Longitude 5.6 mm. ; X4. 291 



F'&- 5- Siphonalia kellettii Forbes. Upper San Pedro series, San Pedro. Longitude 112 



mm. ; natural size. 229 



Fig. 6. Nassa versicolor var. hooveri, var. nov. Upper San Pedro series, San Pedro. 



Type specimen. Longitude 14 mm. ; X2.7. 362 



Fig. 7. Fustis riigosus Trask. Lower San Pedro series, Deadman Island. Longitude 



50 mm. ; X1.3. 226 



Fig. 8. Seila assintilata C. B. Adams. Lower San Pedro series, San Pedro. Longitude 



ID mm.; X4- 290 



Fig. 9. Marginella ( Volvarina) varia Sovverbv. Lower San Pedro series, Deadman 



Island. Longitude 9.2 mm. ; X2-6. 222 



Fig. 10. Mitromorpha internicdia, sp. nov. Lower San Pedro series, Deadman Island. 



Type specimen. Longitude 9.6 mm.; X4- 223 



Fig. II. Bitiimn riigatum Carpenter. Upper San Pedro series, San Pedro. Longitude 



13 mm ; X3-i- 295 



Fig. 12. Rissoa acutelirata Carpenter. Upper San Pedro series, San Pedro. Longitude 



2.1 mm.; X6.7. 305 



Fig. 13. Ttirri/el/a Jewe/tii C\K?B.nTRTL. Pliocene, Deadman Island. Longitude 69 mm.; 



natural size^ 300 



Fig. 14. Odostomia ( /vara) lerricula (Carpenter) D. & B. Lower San Pedro series, 



Deadman Island. Longitude 4 mm.; X6-7- 285 



Fig. 15. Fusus barbare7isis Trask. Pliocene, Deadman Island. Longitude 50 mm.; X1.5. 224 



