﻿260 DESCRIPTIONS OF 



has kindly sent me suites of this interesting Unio without the soft parts, but 

 recently both he and Prof. Holmes, of Charleston, S. C, have kindly supplied me 

 with perfect specimens in alcohol, which enabled me carefully to examine the soft 

 parts and to describe them. Unfortunately neither of seven specimens received had 

 ova, so that the form of the embryo or that of the branchial uterus could be described. 



Anodonta Senegalensis. PI. 41, fig. 140. 



Testa lsevi, transversa, subinnata, ad latere vel planulata vel compressa, ad basirn subemarginata, valde 

 inasquilaterali ; valvulis crassiusculis ; natibus subprominentibus, ad apices minute et oblique undu- 

 latis ; epidermide tenebroso-viridescente, nitida, eradiata; margarita vel cseruleo-alba vel salinonis 

 colore tincta et iridescente. 



* 

 Shell smooth, transverse, rather inflated, flattened or compressed at the side, sub- 



emarginate at the base, very inequilateral ; valves somewhat thick ; beaks somewhat 

 prominent, minutely and obliquely undulate at the tip ; epidermis dark green, shining 

 and without rays ; nacre bluish white or salmon color and iridescent. 

 Anodonta Senegalensis, Lea. Proc. Acad. Nat. Sci., 1859, p. 154. 



Hob. — Senegal. J. C. Jay, M. D., E. Verreaux and H. Cuming. 



My cabinet and cabinets of Dr. Jay, Mr. Verreaux and Mr. Cuming. 

 Diam. 1*1, Length 1*5, Breadth 3-4 inches. 



Shell smooth, transverse, rather inflated, flattened or compressed at the sides, 

 subemarginate at the base, very inequilateral, dorsal and basal lines nearly parallel, 

 obtusely angular behind ; substance of the shell somewhat thick ; beaks somewhat 

 prominent, minutely and obliquely undulate at the tip ; ligament long, narrow and 

 dark brown ; epidermis dark green, inclining to olive, shining, without rays and with 

 distant marks of growth ; umbonial slope somewhat raised and rounded ; posterior 

 slope raised into a keel and with two slightly impressed lines on each valve, from the 

 beaks to the posterior margin ; dorsal line with a small longitudinal callus in the left 

 valve under the beak ; anterior cicatrices large and distinct, the inferior one being 

 very large in proportion and transverse ; posterior cicatrices large and confluent ; 

 dorsal cicatrices single in each valve and placed nearly in the centre of the cavity of 

 the beaks ; cavity of the shell rather deep and rounded ; cavity of the beaks very 

 shallow and subangular ; nacre bluish white or salmon color and iridescent. 



Remarks. — I have had a young shell of this species in my collection received many 

 years since from Dr. Jay. Subsequently, in 1853, I procured a still younger one from 

 Mr. Verreaux in Paris. More recently I recognised two adult specimens among the 

 Unionida? sent to me by Mr. Cuming from his collection. The oldest of these is nearly 

 three and a half inches wide and is quite a thick shell, and the nacre finely tinted 

 with salmon color. The younger ones are thin and light, and of a bluish white nacre 

 and lighter green epidermis. The beaks of all but two young specimens are eroded 



