662 



MOLLUSCA 



PHYLÜM VI 



Goeloceras (Deroceras Hyatt) (Fig. 1279), Dadylioceras (Fig. 1280) and Peronoceras 



Hyatt ; Pimelites and Diafliorites Fucini ; 

 (?) Praesphaeroceras Levi ; (?) Gollina Buckm. 

 Middle and Upper Lias. 



Subfamily B. Stephanoceratinae 

 Steinmann. 



Fi(i. 1280. 



Dactylioceras commune (Sovvb.). Upper Lias 

 England. 



Primitive radicals, highly coronate, dis- 

 coidal, giving rise ai)parently to involute and 

 partially comjiressed forms that in Macro- 

 cephalites and some otliers are without tubercles, 

 Venter always rounded, costae bifnrcating on 

 the sides and continuous acroßs tlie venter. 

 Only one line of nodes or tubercles at tlie 

 umbilical Shoulders, and the division of costae 



Fig. 1281. 



SpJuxerocerasbrongniarti (Sowb.). Inferior 

 Oolite ; Bayeux, Calvados. 



Fk;. 1282. 



Normannitcs braikenridgei (Sowb.). In- 

 ferior Oolite ; Bayeux, Calvados, i/i. 



takes place along these lines in most forms. Sutures of the same type as in Dacty- 



Fic. V2S3. 



Af«r»e„A„«,» M^r„o,p„a,u. (Scl.lotl,.,. Upp» Doggor (Callovian) ; Ehninge,,, Würtcmbsrg. 



lioidmae, l.ut nnich more complex, with usually „lore iniiections, and lote and saddle. 



J 



