CEPHALOPODA— AMMONOIDEA. 1 59 



CIX. Clionites Mojsisovics. 

 Slightly embracing, with subquadrangular whorls, of equal 

 breadth and height ; venter with central furrow ; side with strong 

 ribs bearing spinous nodes ; sutures ceratitic with rounded saddles, 

 entire or slightly serrated external lobe divided by low, siphonal 

 saddle; strongly serrated lateral, and auxiliary lobe on umbilical 

 shoulder; young like Tirolites. Triassic. 



255. C. fairbanksi Hyatt and Smith. Triassic. 

 Ribs broad, very spinous in old age ; broken into two rows of 



coarse nodes near ventral furrow; sides flat. 

 Upper Triassic of Shasta County, California. 



256. C. (Traskites) robustus Hyatt and Smith. (Fig. 1406, d-h.) 



Triassic. 



Broader and more robust than the preceding, with more strongly 

 rounded venter ; nodes finer, more spine-like ; margined by strong 

 spines. 



Upper Triassic (Hosselkus limestone) of Shasta County, Cali- 

 fornia. 



ex. Trachyceras Laube. 



Compressed; moderately umbilicated; whorls deeply embracing, 

 higher than wide; umbilical shoulders abrupt, narrow, furrowed; 

 venter bounded by rows of tubercles (a single one on each side in 

 Protrachyceras) ; surface with fine ribs radiating from umbilical 

 tubercles; and ending in ventral rows of tubercles, having addi- 

 tional rows of tubercles on sides; suture ammonitic (ceratitic in 

 Anolcites). Triassic. 



257. T. (Protrachyceras) lecontei Hyatt and Smith. (Fig. 1407, 

 a-c.) Triassic. 

 Umbilicus small ; sides compressed, gently curving ; whorls very 



high ; ventral furrow with a single row of tubercles on each side ; 

 radiating strise fine ; spiral rows of nodes coarser than radial ; 

 sutures passing from goniatitic directly into ammonitic stage. 

 Upper Triassic (Karnic) of Shasta County, Cahfornia. 



258. T. (Anolcites) meeki Mojsisovics. (Fig. 1407, J-/.) Triassic. 

 Umbilicus wide and deep; ventral furrow deep; ribs strong 



and curving, spiral row of nodes weaker; suture ceratitic with 

 entire rounded saddles. 



Middle Triassic, West Humboldt Range, Nevada. 



