47 8 



ODONTOTROPIS. 



GENUS 136. ODONTOTROPIS GRUN, 1884. 



Valve biddulphoid, 

 furnished with two long 

 aculeate horns, con- 

 nected by a pectinate, 

 dentate or smooth keel. 



This genus includes 



about half a dozen curious 



forms, two of which, O. 



carinata Grun. and O. 



cristata, are found in the 



Cemenstein of Mors. 



Figure 210 in the text represents O. crisiata. It has unfortunately been 



made from an imperfect specimen. It should appear as if the right side was 



similar to the left, and the dentated comb should extend throughout the 



surface, which separates the two horns. 



Fig. 210. Odontropis cristata. 



GENUS 137 KERATOPHORA PANT., 1889. 



Valve biddulphoid, broadly elliptic, with coarse puncta, furnished 

 with two very long robust, tortuous horns, often bifurcated. 



Fig. 211. Keratophora robusta. 

 a. Valve view. & Girdle view. 



