﻿244 ME. E. BULLEN NEWTON" ON EOSSIL [May 10,10, 



the late Prof. Drummond, in 1888, as ' a single species of the 

 Tellinidse,' which indicated a family of marine shells ; but when 

 they were subsequently examined by Prof. T. Eupert Jones, he was 

 enabled to describe them as of freshwater origin under the genus 

 Iridina(?). Later still, Prof. Amalitsky included the species of 

 Iriclince (?) of Sharpe and Jones in his genus Palceomutela, for which 

 and other genera he founded the family name of Anthracosidse 

 or Paheounionidse. 



Several estuarine or freshwater mollusca are now recorded from 

 the Karroo deposits of Africa, owing chiefly in more recent years to 

 the researches of Prof. Amalitsky, who, after studying the types 

 •contained in the British Museum and in the collection of the Geo- 

 logical Society, relegated them to his new genera Palceomutela and 

 Pcdceanodonta, and demonstrated their unmistakable resemblance to 

 the Permian freshwater shells of Russia, five species being found 

 alike in the two countries (see Distribution Table, p. 246). 



Formation. — Permo-Carboniferous [Karroo Beds]. 



Localities. — Nkana (Andrew & Bailey); Maramura (Drum- 

 mo nd). 



Palaeozoic Crustacea (Phyllopoda). 



Genus Estheeiella, C. E. Weiss. 



Zeitschr. Deutsch. Geol. Gesellsch. vol. xxvii (1875) p. 711. 

 Type = Posidonomya loengensis, Giebel. 



Distribution. — The Triassic of Saxony, etc. ; Permo-Carbo- 

 niferous of South Africa ; and the Upper Carboniferous of Scotland. 



Estheeiella nyasana, sp. nov. (PI. XIX, figs. 15-18.) 



Description. — Valves small, more or less depressed, oblong, 

 narrow, sometimes subquadrate, moderately and regularly convex. 

 Umbones antero-terminal. Dorsal line extended, straight, slightly 

 oblique, nearly parallel with the ventral border ; anterior margin 

 truncated, straight; posterior margin with outward curvature. 

 Ornamentation comprising about twelve equidistant concentric 

 striations with a finer series occupying the interspaces, crossed 

 by obscure radial riblets ; surface more or less wrinkled, and 

 covered with pittings or granulations. 



Dimensions. — The valves measure about 1 millimetre in their 

 longest axis. 



Remarks. — At the reading of this paper before the Geological 

 Society, I was under the impression that the obscure fossils now 

 described might represent the embryonic condition of the associated 

 shells of Palceomutela (?), and I therefore referred to them as 

 belonging to the glochidial stage of that pelecypod. Erom a further 

 study of the specimens, however, and assisted by some excellent 

 camera lucida drawings made by Mr. Highley, I regret that I am 

 no longer able to support so interesting an interpretation, being 

 convinced that these little fossils are the carapace-valves of a 

 phyllopodous crustacean generally known as the genus Estheria. 



