﻿PSEUDOSPATHA 205 



At the time of publishing the Synopsis I had not been able 

 to see the paper containing this species and the name was 

 given erroneously in my work. The shell is something like 

 P. livingstonensis, but the beaks are not placed nearly so close 

 to the anterior end as in that species. 



PsEUDOSPATHA LIVINGSTONENSIS (Bourguignat) . 



Shell thin, compressed, elongated, when young, narrow be- 

 hind and drawn out into a long beak ; when old the dorsal and 

 basal lines are nearly parallel and the shell is rhomboid ; pos- 

 terior ridge double ; there is a posterior and anterior wing, 

 below the latter the shell is slopingly truncate ; surface pale 

 coppery, slightly concentrically ridged ; beaks low, compressed, 

 with concentric sculpture, which becomes nodulous near the 

 embryo, showing the nepionic shell ; there is one pseudocar- 

 dinal and one lateral in each valve ; beak cavities shallow, with 

 an irregular dorsal scar well behind the pseudocardinals ; ad- 

 ductor scars shallow ; nacre purplish, somewhat iridescent be- 

 hind. 



Length 115, height 45, diam. 15 mm. 



Lake Tanganyika. 

 Spatha tanganyicetisis Smith (part), Proc. Zool. Soc. Lond., 



1880, pi. XXXI, fig. 8a; 1881, p. 296, pi. xxxiv, fig. 32. 

 Biirtonia liinngstonensis Bourguignat, Moll. Fluv. Nyanz., 



1883, p. 20. 

 Pseudospatha livingstonensis Simpson, Syn., 1900, p. 578. 

 Pseudospatha limngstoni Germain, Moll. L. Tan., 1908, p. 686. 

 Burtonia elongata Bourguignat, Un. and Ir. Tan., 1886, p. 34 ; 



Icon. Mai. Tan., 1888, pi. xxv, fig. 3. 

 Burtonia contorta Bourguignat, Un. and Ir. Tan., 1886, p. 39; 



Icon. Mai. Tan., 1888, pi. xxvi, figs. 3-5. 

 Burtonia hridouxi Bourguignat, Un. and Ir. Tan., 1886, p. 



40. — Simpson, Syn., 1900, p. 578. — Germain, Moll. L. Tan.. 



1908, p. 687, figs. 41, 42. 



The shell gapes considerably at the front and anterior base 

 and slightly behind. The line of juncture between the valves 



