﻿52 r,AMPSILlS 



Lampsii.is DLii.uMBis (Coiirad). 



Shell long- ovate, very thin and f rag^ile, ventricose ; Ugament 

 margin slightly elevated ; anterior side rather narrow ; poste- 

 rior margin rounded ; epidermis olivaceous, with green rays ; 

 umbonal slope rounded ; beaks only moderately full ; margin 

 of the ligament slope rounded, very oblique ; within bluish, 

 highly iridescent ; cardinal teeth lamellar ; cavity capacious. 

 Length 54, height 30 mm. 



Type locality, small streams near Cooper River, South Car- 

 olina. 



Unio delumhis Conrad, New F. W. Shells, 1834, p. 35, pi. v, 

 fig. 3. — Chenu, Bib. Conch., ist ser.. Ill, 1845, p. 18, pi. 11, 

 fig. 10. 

 Lampsilis delumbis Simpson, Syn., 19CXD, p. 531. 



1 have never seen this species that I know of, and am some- 

 what uncertain as to its relationships, as Conrad says nothing 

 of its beaks or their sculpture. My description of the species is 

 made up from his description and figure. He gives no meas- 

 urements, but it is |)robable that his figure is life-size, as are 

 the rest of them in the New Fresh Water Shells, and I have 

 given the measurements of this figure. It is possible that this 

 may belong to the group of /,. iris. It looks something like an 

 elongated L. ochracea. 



Lampsius PEROVALis (Conrad). 



Shell rather solid and inflated, obovate rather short; beaks 

 high, but only moderately full, situated about two-fifths of the 

 distance from the anterior to the posterior end ; their sculpture 

 consists of strong, slightly doubly-looped ridges ; posterior ridge 

 well developed and ending in a blunt point behind about mid- 

 way up from the base ; epidemiis greenish-yellow or greenish- 

 tawny, with faint rays, smooth and shining in the middle of the 

 disk, a little wrinkled and duller colored at the ends ; left valve 

 with two rather strong pseudocardinals in front of the beak, 

 which are rather solid and slightly compressed, the anterior 

 the higher; there are two short, distant laterals, the lower the 



