Mollnsca froui tJie Bokkevcld Beds. 251> 



Dimensions. — Length 22 mm. ; height 9 mm. 



Affinities. — This species is alUed to Nuculites oblongatus, Conrad/" 

 but is relatively more elongate and has the clavicular ridge directed 

 obliquely backwards instead of being vertical. N. solenoides, Gold- 

 fuss, f has a somewhat similar shape, but narrows too rapidly towards 

 the posterior end ; the clavicular fold is oblique as in our new- 

 species. 



Localiti/.—{No. 93) Gamka Poort. 



NUCQLITES? OVATUS (Sharpe). 



1856. Lcptodomus ? ovatus, Sharpe, Trans. Geol. Soc, ser. 2, 

 vol. vii., p. 212, pi. xxviL, fig. 7. 



Sharpe described this species as follows : " Shell transversely 

 ovate ; anterior end thick and truncated, posterior end produced and 

 gradually thinning down to the rounded posterior margin : two very 

 slight furrows extend from the beak to the posterior end; beaks 

 large, rounded, and close to the anterior end : valves covered with 

 concentric lines of growth. Length 1\ inches ; breadth If inches ; 

 thickness 1 inch." 



Sharpe's figure makes the shell look rather too triangular ; the 

 posterior end is broader and less pointed, the cardinal margin being 

 less oblique than represented. The beaks are also more obtuse and 

 rounded. The shape of the shell is distorted owing to crushing and 

 imperfect preservation, but the disproportion in the height of the 

 anterior and posterior ends is certainly exaggerated in the figure. 



The true generic position of this species is doubtful, and we have 

 unfortunately only the single type specimen on which to determine 

 it, which gives us no information about its internal structure ; but it 

 is not improbable that it belongs to the genus Nuculites. 



Locality. — Leo Hoek (Leeuw Fontein, Warm Bokkeveld). 



NUCULITES COLONICUS sp. nov. 



(PI. XXXIL, fig. 1.) 



A left valve (No. 69) of a small species of Nuadites in the condi- 

 tion of a cast appears to belong to a different species to any of the 

 foregoing. The shell is elliptical, with the anterior and posterior 

 ends rather pointed, the basal margin arcuate, the cardinal margin 



* Hall, o;). cit., pi. xlvii., figs. 1-12, p. 324. 



t Goldfuss, Petref. GermaniEe, (1840), p. 144, pi. cxxiv., fig. 9. 



