664 MOLLUSCA 



1288) ; Ätaxioceras Font.; FroplamiUtes Teiss.; Pidonia Bayle ; 

 Lampl. Inferior Oolite and Cretaceous. 



PHYLUM VI 



Pavl. and 



FiCr. 1286, 



Suture line of Perisphindes colubrinus 



(Rein.). 



Fi(i. 1287. 



Perisphinctes polyplocus (Rein.). Upper 

 Jura ; Pappenheim, Bavaria. i/g. 



Perisphinctes tiziani (Oppel). Upper Jura (Bimammatus Beds) ; 

 Hundsrück, near Streichen, Würtemberg. 



Subfamily E. Morphoce ratin ae Hyatt. 



Globose and iisually involute fornis witli open umbilici showing the yoimg to be 

 highly coronate imtil a late stage. Costae on iimbilical zones Single and widely 



separated, but divided into 

 very broad biindles of fine, 

 closely - set, ventro - lateral 

 costae diflering from those of 

 all other groups except sonie 

 Perisphinctinae. Only one 

 line of tubercles or nodes, 

 whicli usually occiir at um- 

 bilical Shoulders. External 

 and dorsal sutures resemble 

 those of Perisphinctinae, but 

 not so imiformly inclined 

 apicad. In discoidal coronate 

 Shells the lobes and saddles 

 are of equal length, and 

 dorsum has two pairs of 

 zygous lobes and two pairs of 

 saddles. 



Morphoceras Douv. ; 

 Garantiana Siemirad. ; Olco- 

 stephanus Neuni. {Holcostephanus aiict.) ; Folyptijchites, SimhirsJdtes, Ästieria, and 

 Virgatites Pavl. and Lampl. Upper Jura and Cretaceous. 



Fi(i. 1289. 

 ReinerJcia hrancoia (Steinm.). Caracoles, Boliva (after Steiiimann). 



