OH I iKK II 



AMMONOIDEA 





Tetrayonites, /V,/, /,//, ////,/,>, K-.-.mat : ^/./m//-//.-. /"-, < Ii-.. .MVIV : /'/ ' 

 , f en. nov. Type P. (A nun.') </"<"///- 

 * nli-it hi*, <\'< )rli. sp. ( 'ivtareous. 



Family 3. Haploceratidae. 



Zittel. Mostly involute >hells, 



smooth, or with constriction.- an 1 



fold-like, costae without tubercles 



that commonly follow the line- ot 



growth across the rounded venter 



uninterruptedly. Spines -onie- 



tiines present as in preceding 



family. Sutures have blunt 



siphonal -addles, never pointed. 



First lateral lobes shallower than 



in Lytocf.ratidar, the first lateral 



saddles broader, and le-s deeply 



cut by marginals. Anti-iphonal 



lob.- long, straight, and tritid. 



Lateral zygous inflections more 



numerous, and there are often 



three or more zygous dorsal 



saddles. 



Haploceras, Zittel (Lissoceras, 



Bayle), (Fig. 1175). Jura and 



Cretaceous. Eurynoticeras, Cana- 



vari. Jura. Desmoceras, Zittel 



(Figs. 1176, 1177); Puzosia, 



Bayle ; Cleonoceras, Paroni and 



Bon. ; Schlueteria, Hauericeras, Grossouvre. Cretaceous. 



F a in i 1 y 4. 

 Glochicera- 

 tidae. Discoidal 

 and involute 

 shells, smooth in 

 ]> r i m i t i v e 

 -peri,-, but ac- 

 quiring highly 

 inflected cost a - 

 timi.-, -oiiietinu-^ 

 with two rows of 



tubercles on the sides, and a median ventral row that may fu-e into a continuous 



solid keel. One line of ventral tubercles may also arise 



directly from folds that appear in otherwise unornaniented 



shells. Aperture sometimes with long lateral lappets similar 



to those of Oppelidae. Sutures .-imilar to Haploceratidae. 

 Cadomoceras, Creniceras, Mun.-('halm. (Fig. 1178); Cyrto- 



siceras, gen. nov. (Fig. 1179). Type C. (Amm.) macro- 



telus, Oppel sp. ; Glochiceras, gen. nov. (Fig. 1106). Type G. 



(Amm.} nimbatum, Opp. sp. ; Phlycticeras (Lophoceras, Bonar. . 



Ochetoceras, Haug (Fig. 1180); Cymaceras, Quenst, (Hyatt). 



Type C. (Amm.) Guembeli, Opp. sp. Strigocems, Quenst. (Buck- 

 man); Streblites, gen. nov. (Fig. 1181). Type S. (Amm.) 



pictus-costatus, Quenst. sp. Middle and Upper Jura. 



Desmocerns Mayorianum, 

 (after d'Orbigny). 



Gault ; I'erte ilu Rhone 



Suture-line of Desmoceras Jut;ii'n-!if<i,it, Mjch. Gault; Perte 

 u Hli< me. 



Km. 117S. 



Oppel. sp. Oxfordian ; 



Salins, .lura. 



Fio. ii7;>. 

 Cfrrtwfaww macro* 



