634 



MOLLUSCA 



PHYLUM VI 



Family 8. Pinaooceratidae Mojsisovics. 



Forms vntli involute, compressed, hi(jh ivhorls, vnth narrow and often acute venters. 

 Body-chamher short. Septa goniatitic to ceratitic, to digitate, but always with adventitious 

 and auxiliary lobes in addition to the regular series. 



The group is probably derived from tlie Beloceratiiiae, at least in so far as it is 

 a unit. This is almost certainly true of the Sageceratinae and the Hedenstroeminae ; 

 the Carnitinae are probable derivatives of the Hedenstroeminae, and the Pinaco- 

 ceratinae apparently are derivatives from the Sageceratinae. 



Subfamily A. Hedenstroemiinae Waagen. 



Principal lobes and saddles with ceratitic outlines, but adventitious lobes and 



saddles have Sageceras -like outlines. 

 Antisiphonal lobe bifid and very long. 

 Dorsal inflections more complex than 

 in preceding families. Aperture with 

 ventral crests. 



Hedenstroemia Waagen (Glypites 

 Waagen) (Fig. 1189); Prodromites 

 Smith and Weller (Fig. 1190); 

 Aspenites H. and S. ; Longobardites 

 Mojs. Carboniferous to Trias. 



.:fy 



VV^Ii^^ 



J-f' 



'n(^xA. 



U' 



'-.C'7 <£■ : 



Fio. 1189. 

 Hedenstm-mia. hissmati H. and 8. Lower Trias ; Idalio. 



Fig. ll'JU. 



Prodromites gorhyi Miller. Lower Carboni- 

 ferous ; Missouri. 1/2 (after J. P. Smith). 



Subfamily B. Sageceratinae Hyatt. 



Similar to the last, but lateral lobes bifid, and saddles acutely spade-shaped. 

 Adventitious and auxiliary lobes numerous. Antisiphonal lobe bifid. Aperture has 

 sinuous lateral outlines with crests at the A'entro-lateral ridges. 



Pseudosageceras Diener (Fig. 1191); Sageceras Mojs. (Fig. 1192). Permian and 

 Trias. 



