RHABDOrEKAS, BACTR1TES, ETC. 219 



Genus BACULINA, d'Orb. 



Shell straight, point conical ; sutures of septa a row of rounded 

 lobes, toothed at base. 



Two species. Jurassic, Lower Chalk. Europe. 

 B. ARCUARIA. Quenstedt. PI. 100, fig. 517. 



Genus RHABDOCERAS, Hauer. 



Shell straight, orthoceratoid, strongly sculptured; septa with 

 rounded lobes. 



One species. Alpine Triassic. Germany. 

 K, SUESSII, Hauer. PL 100, figs. 513, 514. 



Genus BACTRITES, Sandbergcr. 



Shell straight; sutures lobed. 

 Three species. Devonian. Germany. 

 B. GRACILIS. Sandb. PL 100, fig. 515. Nassau. 



Genus TOXOCERAS, d'Orb. 



Shell horn-shaped or curved ; the six lobes and saddles of the 

 sutures simply crennlated ; last chamber large. 



Twenty species. Neocomian, France. 



Connected with Crioceras and Ancyloceras by numerous in- 

 termediate forms. 



T. BITUBERCULATUS, d'Orb. PL 100, fig. 52f>. 



Genus HAMTJLINA, d'Orb. 



Differs from Hamites in being only once bent upon itself, not 

 in contact. Perhaps should not be separated from Hamites. 



Twenty species. Neocomian. France; Grault (?). India. 

 H. TRINODOSA, d'Orb. PL 101, fig. 5:>f>. 



Genus HAMITES, Parkinson. 



Shell conical, hook-shaped, bent upon itself more than once, 

 the courses separate. 



Thirty-eight species. Chalk. Europe; S. America. 

 H. ATTENUATUS, Sowb. PL 101, fig. 533. England. 

 H. CYLINDRACEUS, Defr. PL 101, fig. 534. 



