DR. P. P. CARPENTER ON THE SHELLS OF PANAMA. 31 



509. Corbula, sp. ind. b. Dead valves of C. biradiata, No. 503. 

 To the same species may be referred C. polychroma. We were mis- 

 led by the different appearance of the dead shell, and by the locality- 

 mark in Col. Jewett's collection. His specimens were probably from 

 Panama or Acapulco. 



510. Solecurtus affinis, M. 37. It is probable that this species 

 is identical with S. (tNovaculina) caribbceus. The Ariquibo speci- 

 mens of the latter in Mus. Amherst are more like the Mazatlan shells 

 than those are to the Panama type. Shells from Cape Palmas were 

 affiliated to the Caribbsean species by Mr. Cuming. 



511. Solen rudis=Ensatella r. This interesting form passes 

 towards Pharella. It is called " Solena cbliqua, Spengl., var." in 

 Mus. Cuming. 



512. Pholas crudgera. With the general aspect oiBarnea Candida. 



513. Pholas tubif er a=- P holadidea t. Of the melanura type, with 

 a solid tube fitting on to the ends of the cups. 



514. Pholas xylophaga. Of the Martesia type, without cups. 

 Dorsal and ventral plates long ; umbonal plates moderate ; wave of 

 the adolescent gape rather suddenly arched. 



515. Pholas , sp. ind. a. Col. Jewett's specimens of the 



same shell are named laqueata by Mr. Cuming. It is of the non- 

 waved, concameroid type; without radiating sculpture; concentric 

 lamellae beautifully frilled. 



516- Pholas, sp. ind. b. So like P. dactylus that it might be 

 taken for a worn valve from ballast. The sculpture-ridges are, how- 

 ever, further apart ; hinge-chambers larger and more numerous, with 

 a little twisted lamina beyond ; gape less conspicuous. 



517. Orbicula cumingii Discina c., M, 14. 



The shells unfortunately are all loose, in trays, with the autograph 

 names on tickets. Prof. Adams's West Indian collections are in the 

 same condition ; and both series are arranged together, in zoological 

 order, in the midst of the general collection. There is no evidence, 

 however, that they have been handled since the Professor left them, 

 none of the leading conchological writers in the New World having 

 thought it needful to go out of their way to complete a review of the 

 Professor's work. Amherst is situated on a branch railway, and is 

 within an easy walk of Northampton, Mount Holyoak, and the deli- 

 cious scenery of the Connecticut River. In the College buildings 

 are also deposited the most complete series of the Fossil Footprints 

 of the Connecticut River, and the mineralogical collection (including 

 the meteorolites) belonging to Prof. Shepnera. 



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