44 MAZATLAN BIVALVES 



atus, without seeing the slightest approach to these characters, 

 I am obliged for the present to consider them specific. Size 

 of the Mazatlan specimen ; low. '55, lat.*95, alt. '33. Ordin- 

 ary size, as in D. carinatus. 

 Hob. Mazatlan ; 1 young specimen ; L'pool Col* 



Tablet 139 contains this specimen, and two valves, probably 

 from the Central American coast. 



73. DON AX TE AN S VERSUS, SoiV. 



Tank. Cat. App. p. 4, no. 226. Rve. Conch. Icon. pi. 6, sp. 36. 



Known from D. scalpellum, Gray, (Gulf of California) by 

 the peculiar incurving of the anterior dorsal line ; and by the 

 character of the posterior area, which has at the margin one 

 large and two small flexures, while the surface is covered with 

 radiating stria?, very finely and granularly serrated. Long. ' 56, 

 lot. 1*34, alt. '3. 

 Hob. Mazatlan ; extremely rare ; teste R. Tyler, Esq., who 



found a fresh valve concealed in a Chama from the L'pool 



Col. The other valve is nowhere to be found. 



Tablet" 14D contains this valve, most kindly presented by 

 Mr. Tyler. 



74. DONAX ASSIMILIS, Hani. 



Proc. Zool. Soc. 1845, p. 17. C. B. Ad. Pan. Shells, p, 277. 



no. 454. Rve. Conch. Icon. pi. 2, sp. 10. 



This species is used for food at Panama, where the natives 

 scoop to its depth, and keeping to the same level find them in 

 great abundance. (C. B. Ad.) Long. '92, lat. 1*36, alt. '51. 

 Hob. Panama, Mus. Cuming. Do. very plentiful, a few inches 



deep in sand at 3-4ths tide level, C. B. Adams. Mazatlan, 



Lieut. Green. Mazatlan ; 1 valve only ; L'pool Col. 



Tablet 141 contains the solitary valve. 



75. DONAX PUNCTATO-STEIATUS, Hani. 



Proc. Zool. Soc., 1843, p. 5. Eve. Conch. Icon. pi. 3, f. 16. 

 Var.=~D. radiatus Vol. in Humb. Rec. vol. ii, 1833. 

 ?=D. flexuosus, Gould's plates. 



* An extremely similar shell is given in the Bristol Museum as Donax rugosue, 

 Dr. Cutting, W. Indies. 



