A.M.MHNOIDKA 





Family 0. Ptychitidae. Similar in aspect to primitive form- of G 

 lull having subacute venter.-, le complex sutures and the aii\iliar\ 

 i- in rrfoiiitii/"'. /'/;/<////, x 



Fig. 1141), J(l Jim, it , x, 



Mojs. ; Pseudodan ni>it, .<, gen. 

 nov. Type P. (Danub. 

 ,1 ritn rxh tru, Diener sp. 

 Trias. 



Family 7. Aegocera- 

 tidae. Neumayr restrict.". 

 Smooth, compressed, dis- 



roidal shells with rounded 



venter in primitive forms, 



becoming involute with 



acute venter in specialised 



-pecies. Suture.- similar in 



convexity and general aspect 



to iliose of Pinacoceratiilm , 



but having peculiar, highly 



inclined auxiliaries which 



are developed apparently 



from marginals on the um- 

 bilical sides of the saddles ; 



no corresponding adven- 

 titious inflections. Siphonal 



saddle similar to that of 



Prionitidae, and arms of the ventral lobe narrow. First lateral saddles are dependent 



on, or attached to the large siphonal saddle-, 

 and often simulate adventitious saddles. 

 Aeyoceras, Waagen, s. str. (V .'//////*//'.-, 

 (Fig. 1142) ; Biiddhaites, Diener 

 gen. nov. Type A. (Gym.) Lamarcki, Diener 

 sp. Paragymnit&i gen. nov. Type P. (/' 

 .tiikinitiild, Moj-. -p. Ti'ias. 



Family 8. Hungaritidae. Involute 

 forms with keeled or more or le-s acute venter. 

 Ventral lobes remain undivided in some forms 

 until a late stage of growth. Specialised shell- 

 have a more or less extensive series of auxil- 

 iaries, and a few adventitious inflection- 

 derived from division of the siphonal saddle. 



lliiinjuriii'x, (\trn //(.>-, Longobarditet) M'>j-. ; 

 Noetlingites, gen. nov. Type A". II" mi. X/ /.////- 

 //''/.-/, (Jrii-peiik >p. : Zforttes, gen. nov. T\ p.- 

 I. (Hung.) Pradoi, Mojs. -p. Trias. 



Fie. 1141. 



Ptyclii 



H;IIUT p.p.). Musdiclkalk ; 



Fio. 1142. 



Aegoceras ( = 

 kalk ; Schreyer Alp, near Gosau, Austria 



III. CERATITIDA. 



Primitive form* i/i*<'/i/<l<tl, i'o///y//-<xxM/, ////</ }mn >// /;//<> ii-ith n/iil/rnl'd ri/i/rttl lobes; 

 specialised forms linn tin lufd-i- diridnl^ ,i,/<l x/c7/s more or less inrnl nfr, l*o more or less 

 nodose or costatecL S" <t</l<* are of the fti/n'cul discophyllie form, the lobm //x/'<///// n.rron-, 

 denticulated, long, and broadening more or less at the ajn'rul ,//</.<. I*. //'/v// /--//, x in tl,,:- 

 are apt to be very broad and shallow, witli (Iriitirnlufnl amtc, mul .<m<ilt /////// 

 saddles. 



