﻿NEPHRON A I AS 273 



Unio proclinatiis von Martens, Biol. Cent. Am., Moll., 1900, 



p. 508. 

 Unio gundlachi vSowerby, Conch. Icon., XVI, 1866, pi. xevi, 



fig. 248. 



I am satisfied that there are at least tw.o species of Naiades 

 in Cuba, but it is very difficult without access to the types to 

 say what names should be applied to them. The descriptions 

 oif Unio scamnatus by Morelet and U. gundlachi by Dunker 

 are in Latin and inadequate to satisfactorily characterize these 

 difficult and probably closely related forms. Von Martens, be- 

 lieving that the names of Morelet and Dunker both apply to 

 one species and that there are two diagnosible forms in the 

 island, has applied a new name, Unio proclinatiis, to the form 

 I have described as A', scaumata. Morelet states that the car- 

 dinals of his shell are subtriaugular, that the epidermis is ful- 

 vous-chestnut, and these are two characters, which apply to 

 the species I have described and not to what I incline to 

 believe is Bunker's species, which has a brownish-green epi- 

 dermis and compressed pseudocardinals. I have examined a 

 large amount of material from Cuba and generally do not have 

 the least trouble in separating the Uniones of that island into 

 the two forms. Usually the species I have described is consid- 

 erably more elongated than the other, though certain male 

 shells approach closely in form ; it is a little less inflated, the 

 outline from a dorsal view showing an even curve from end 

 to end, while that of what I believe to be gundlachi is most 

 decidedly swollen at or behind the middle of the skull. U. 

 scamnata is more strongly and evenly sulcate, the sculpture 

 covering the entire shell, while in gundlachi it is often faint 

 or wanting, especially just in front of the posterior ridge. 

 A', scamnata is rayless or has broad, feeble rays; gundlachi is 

 almost always rayed. And finally the female shell of scamnata 

 appears to be but slightly fuller in the post-basal region than 

 that of the male, while that of gundlachi is always well pro- 

 duced, often as decidedly and extensively so as that of Lamp- 

 silis snhrostrata. 



