•M». OB SCHLOI IIKl.MI \.\ BRAN4 II 126 



TM.EGOCERAS.' 



Tmaegoceras latesulcatum Htj 



Amm fal—fcofm, II mm:. Ceph. d. Lii 



This extraordinary form, found in the red limestones oi Adneth, baa a combi- 

 nation of characteristics altogether distinct from thai of any other species. The 

 form of the whorl, its smooth Bhell, and 1 1 1 « - discoida] mode of growth, are purely 

 ran. 'l'i. re, however, arietian, and more like those ol Caloceras 



than typical Psiloceras or those of any other gen us. We are not aware of it- 

 having been found elsewhere than in the Mediterranean province Hauer 

 appears to think that its affinities may lie with the Arietidse, and that is also our 

 opinion, but until the young have been Btudied it cannot be classified. 



Tmaegoceras levis, Htatt. 



II It, pi iii. li^. 10. 



This i> a sinooih. keeled, and channelled discoida! form like the preceding, 



but dwarfish, like other - this locality. 



PLICATUS STOCK. 



SECOND, OB SCHLOTHEIMIAN BRANCH. 



The living chamber is of uncertain length, though Quenstedl gives it in his 

 "Ammoniten des Schwabischen Jura" as possibly a volution in length in Schlo- 

 iheini i shell is involute in some forma The whorl ie flattened laterally. 



and in oM age became subacute. A bd th median /one or channel was formed 



on tin- abdomen by the suppression of the pike, which were continuous across the 

 abdomen in the preceding nealogic or ephebol There are do geniculae, 



though the pike are very completely developed. The forward bend is necessarily 

 gradual, the whorl never having a sufficiently quad ragonal form for the former 

 tion of abmpl bends or genicular on the edges of the abdomen. The sutures 

 Me those l 



W^EHNEROCERAS' 



The adull •"th median /one along the abdomen. The pike, so far as the 



young are known. cross the abdomen during the earlier nealogic stages, and this 

 charai tied throughout the adult ntnges in some cpecies The smooth /one 



is really an incipient channel, formed subsequently by the resorption of the pike 



This ] take phu ither in the latei , ephebolic, or senili 



] tend to di folds, and 



1 Tn'rrx. » ' 



