Mollusca from tlie Bokkevcld Beds. 247 



HYOLITHES SUB^QUALIS, Salter. 



1856. Tlieca subceqitalis, Salter, Trans. Geol. Soc, ser. 2, vol. vii., 

 p. 215, woodcuts, figs. 3, 4, p. 214. 



The description of this species given by Salter is as follows : 

 " Length ^ inch, width 3 lines. Shell rather thick, quickly tapering, 

 smooth or crossed only by lines of growth ; ventral side gently convex, 

 the dorsal more convex and subangular, but with the angles quite 

 rounded off." 



Affinities. — The species described by Ulrich ''■'■ as H. scliencki from 

 the Devonian of Bolivia is closely allied, as he has remarked. 

 H. ligea, Hall,i from the Schoharie Grit, also appears to bear a 

 considerable resemblance to the Bokkeveld form. 



Locality. — Warm Bokkeveld. 



CONULAEIA AFRICANA, Sharpe. 



1856. Conularia Africana, Sharpe, Trans. Geol. Soc, ser. 2, vol. vii., 



p. 214, pi. xxvii., fig. 13. 

 1893. Conularia africana, Ulrich, Neues Jahrb. f. Miner., Beil. 



Bd. viii., p. 29, t. iii., fig. 4. 



The description of this species given by Sharpe is as follows : 

 "Shell pyramidal with equal sides, each of which has a depression 

 down its middle ; transverse section nearly rectangular, with the 

 corners rounded off and deeply indented ; sides ornamented with 

 numerous parallel pi'ojecting ribs, which in the internal cast are 

 formed of two sharp ridges enclosing a rounded furrow ; the ribs 

 slope upwards towards the middle of the sides, and in the young 

 shell meet at an angle, cross the mesial depression, and slightly 

 overlap one another ; but in the older shells they are continuous 

 across the side of the shell in a curve ; the interstices between the 

 ribs appear to be smooth." 



BeviarJcs. — To the above description it may be added that the 

 transverse section is a parallelogram with rectangular rounded 

 corners ; the longer sides in one specimen (No. 73) measuring about 

 26 mm., and the shorter about 20 mm. The centre of each face is 

 marked dowm the faint mesial depression by a narrow impressed line. 

 The ribs may be continuous across it, or may overlap or alternate in 



* Ulrich, 02>. rit., p. ;^7, t. iii., fig. 9a-d. 



t Hall, op. cit., p. 195, pi. xxxii., figs. 11-16. 



