ORDER Il AMMONOIDEA 5BT 
Family 6. Ptychitidae. Similar in aspect to primitive forms of Gyronitcdae, 
but having subacute venters, less complex sutures, and the auxiliary series straighter, 
asin Prionitidae. Ptychites 
(Fig. 1141), Japonites, 
Mojs.; Pseudodanwbites, gen. 
nov. Type P. (Danub.) 
dritarshtra, Diener sp. 
Trias. 
Family 7. Aegocera- 
tidae. Neumayr (restrict.). 
Smooth, compressed, dis- 
coidal shells with rounded 
venter in primitive forms, 
becoming involute with 
acute venter in specialised 
species. Sutures similar in 
conyvexityand general aspect 
to those of Pinacoceratidae, 
but having peculiar, highly 
inclined auxiliaries which 
are developed apparently 
from marginals on the um- 
bilical sides of the saddles ; 
no corresponding adven- Hie. 1141. 
SLE a : 3 $ Ptychites flecuosus, Mojs. (=Amm. Studeri, Hauer p.p.). Muschelkalk ; 
titious inflections. Siphonal Bele evap SAPD nee A cateial , ; 

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 saddles, 
and often simulate adventitious saddles. 
Aegoceras, Waagen, s. str. (Gymnites, Mojs.), 
(Fig. 1142) ; Buddhaites, Diener ; Anagymnites, 
gen. nov. Type A. (Gym.) Lamarcki, Diener 
sp. Paragymnites, gen. nov. Type P. (Plac.) 
| sakuntala, Mojs. sp. Trias. 
Family 8. Hungaritidae. Involute 
forms with keeled or more or less acute venter. 
Ventral lobes remain undivided in some forms 
until a late stage of growth. Specialised shells 
have a more or less extensive series of auxil- 
iaries, and a few adventitious inflections 
derived from division of the siphonal saddle. 
Hungarites, Carnites, Longobardites, Mojs. ; 
Noetlingites, gen. nov. Type N. (Hung.) Strom- 
becki, Griepenk sp.; Iberites, gen. nov. Type 
Aegoceras (=Gymmnites) Palmai, Mojs. Muschel- ‘ ity ei eee ess 
kalk ; Schreyer Alp, near Gosau, Austria. I. (Hung.) Pradoz, Mojs. sp. Trias. 

Fic. 1142. 
III. CEeRATITIDA. 
Primitive forms discoidal, compressed, ond have sutures with undivided ventral lobes ; 
specialised forms have the latter divided, and shells more or less involute, also more or less 
nodose or costated. Saddles are of the typical discophyllic form, the lobes usually narrow, 
denticulated, long, and broadening more or less at the apical ends. Ventral lobes in these 
are wpt to be very broad and shallow, with denticulated arms, and small divided siphonal 
saddles, 
