264 Annals of the South African Museum. 



-Clarke/'' The general shape of the former, the oblique sulcus and 

 somewhat anterior beak are points of resemblance. But our speci- 

 men is not sufficiently well preserved to admit of a very close com- 

 parison. P. constricta occurs in the Hamilton Beds of the United 

 States, and P. orhignyi in the Devonian of Brazil. In P. sulcata, 

 Hartt and Eathbun,! from the same horizon and region, there is a 

 similar strong oblique sulcus on the surface, but the shell tapers 

 rather more rapidly to the posterior end, and the beaks are less 

 anteriorly placed. 



Locality. — (No. 95) Gamka Poort. 



PAL/EONEILO cf. FECUNDA, Hall. 

 (PI. XXXII. , fig. 6.) 



A left valve of a species of Palaoneilo in the condition of an 

 internal cast (No. 105) may be compared with Hall's species P. 

 fecund a l from the Hamilton Group. The description of our 

 specimen is as follows : Shell ovate-elliptical ; length nearly twice 

 the height ; anterior end regularly rounded ; basal margin gently 

 arcuate ; posterior end doubly truncate ; cardinal margin slightly 

 arcuate (?). Umbo moderate, rising a little above hinge-line, 

 obtuse, situated at about one-third from anterior end. Valve gently 

 convex, especially near umbo, somewhat compressed behind ; 

 unibonal slope flattened, giving slight angularity to shell above 

 and below it, and extending to abruptly truncate posterior basal 

 margin. Several (3-4) strong marginal concentric wrinkles near 

 inferior border ; weak concentric lineation on remainder of valve. 



Dimensions. — Length 46 mm ; height 26 mm. 



Affinities. — The pecviliar angularity of the umbonal slope, the 

 truncation of the posterior basal margin, the position of the umbo 

 and general shape and ornamentation of the shell ally it to P.fccunda, 

 Hall. P. rudis (Sharpe) is shorter and stouter in shape. 



Locality. — (No. 105) Ezel Fontein, Ceres. 



PALiEONEILO sp. 

 (PI. XXXII., tig. 7.) 

 There is the internal cast (No. 96) of one right valve of a shell 



* Clarke, op. cit., p. 74, pi. viii., ligs. 14-17 (especially fig. 14). 



t Hartt and Eathbun, op. cit., p. 124; Clarke, op. cit., p. 75, pi. viii.. tig. 13. 



I Hall, op. cit., pi. xlix., figs. 13, 15-24, p. 336. 



