504 axfx a. olsson 



Explanation of Plate 31 



Figure Page 



1-lb. jDivaricella perparrula Dall 220 



Fig. 1, enlargement of umbonal section; Fig. la, enlargement to 

 show the relatively large, nepionic section with fine, concentric 

 threads, followed by the adult type of sculpture of obtusely 

 bowed, incised lines; Fig. lb, length 21.2 mm. Viveros Island, 

 Pearl Islands, Panama. PRI 25647. 



2. DiTaricella eburnea (Reeve) 220 



Length 16 mm. Pliocene, Punta Blanca, Ecuador. PRI 25648. 



3-3b. Lucina (Parrilucina) mazatianica Carpenter 214 



Copied after Carpenter manuscript drawings, USNM. 



4-4b. Lucina (Bellucina) caucellaris Fhilippi 211 



Fig. 4, copied after Dall, 1901. Length 5.3 mm. Lower California, 

 USNM 96440. Fig. 4a, length 5.2 mm. Pliocene, Punta Blanca, 

 Ecuador. P"RI 25649. 



5. Thyasira excavata Dall 



Copied after Dall, 1901. Alt. 21 mm. Gulf of California, USNM 

 107449. 



6. Codakia (Ctena) chiqnita Dall 218 



Copied after Dall, 1901. Length 10.2 mm. Lower California. USNM 

 96563. 



7. Lucina (Parrilucina) approximata Dall 214 



Copied after Dall, 1901. Alt. 6.5 mm. Gulf of California. USNM 

 96418. 



8-8a. Lucina (Caviling-a) prolon^ata Carpenter 210 



Length 5.5 mm. Puerto Callo, Ecuador. PRI 25650. 



9-9a. Lucina (Parvilucina) mazatianica Carpenter 214 



Fig. 9, length 3.5 mm.; Fig. 9a, length 2.2 mm. Bucaro, Panama. 

 PRI 25651. 



10-lOb. Lucina (CaTilinga) prolongata Carpenter 210 



Copied after Carpenter's manuscript drawing, USNM. 



11. Lucina (Cavilinga) lingiialls Carpenter 211 



Copied after Dall, 1901. Alt. 12.5 mm. Gulf of California. USNM 

 73687. 



12. Lucina (Cavillnga) lampra (Dall) 211 



Copied after Dall, 1901. Alt. 1715 mm. USNM 41626. 



13. Lucina (Pleurolucina) nndatoides Hertlein and Strong 209 



Copied after Dall, 1901. Alt. 10 mm. Gulf of California. 



