TRKM.XTODISCIS. CIMOMIA, ETC. 217 



Submenus Temnocheilus, McCoy. 



Sliell carinated, with an open, conical umbilicus. 

 Five species. Garb, limestone. 



T. BIANGULATUS, Sowb. PI. ( ,)S, fig. 503. 



^ubgenus Trematodiscus, Meek and Worthen. 



Like Temnoclieilu*. but dorsal or outer side of whorls witli 

 revolving angles and snlci, and frequently, revolving striav 



Carboniferous. Europe; America,. 



T. TRISULCATI ;s. Meek and Worthen. PI. 98. fig. 504 a, b. Snb- 

 carbonifemus. Rockford, Inch 



Subgtmis Cimomia, Conrsid. 



Septa sinuous, double waved or sigmoid, numerous; siphon 

 small, central. 

 N. BURTONT, Galeotti. Lower Eocene. 



Subgemis Hercoglossa, Conrad. 



Se])ta angular and linguiform ; apex of the angle or tongue- 

 shaped lobe not contiguous witli the adjacent septum ; siphon 

 large or moderate, situated within the centre, or between the 

 liddle and the inner margin, and not dorsal or funnel-shaped, 

 it tubular and gradually tapering. 

 Eocene. Cret. Europe ; America. 



A very doubtful group, as Conrad includes species having 

 ispectively the characters of Aturia and of Nautilus ; the 

 species, however, N. orbi<-ul(itus of Tuomey, has not been 

 fared. 



Submenus Pseudonautilus, Meek. 



Differs from Hercfxjloxna. in the septa being provided witli a 

 rell-defined peripheral and antiperipheral lobe, and the siphuncle 

 laced near the outer margin. 



NAUTILUS (TEINIT/T, Oppel. 



Subgcnus Cryptoceras, d'Orb. 



Planorbiform ; septa arcuated, without lobes or sinuosities; 

 siphon dorsal. 



Two species. Devonian, Carboniferous. Europe. 



C. SUBTUBERCULATUS, d'Orb. PI. US, fig. 504. 



28 



