1 68 University of Texas Bulletin 



Number of speciiiiens examined: 

 Two. 



Locality: 



Near the top of ridge about 2 miles N 65° W of Wolf Camp at head 

 of valley leading down to tank one-half mile west of Wolf Camp, Glass 

 Mountains. 



W aagenoceras Gemm. 



The genus Waagenoceras has been established by Gemmellaro"^ for 

 ammonoids similar in form to the Triassic Arcestidae. Gemmellaro's 

 original diagnosis says that the species belonging to this group arc 

 covered with fine transversal striae, are more or less globose, involute, 

 and slow-growing, with convex ventral region, narrow and deep um- 

 bilicus; and that the form of the last whorl is different from that of 

 the preceding ones. The internal whorls have two to three internal 

 varices presented as straight and narrow constrictions on the cast, 

 and extending from the umbilicus to the venter. The aperture is low, 

 semilunar, and restricted by a strong and broad internal swelling on 

 the margin; has no lateral ears and no ventral prolongation. Body 

 chamber is one whorl and a half long; suture line curved; siphonal 

 lobe strongly narrowed at the base and deeply divided in two curved 

 branches by a high and broad median saddle. Six lobes exist between 

 the siphonal one and the umbilicus. They are coarsely dentate; be- 

 tween them are seven deeply scalloped saddles which have phylloid 

 ends. 



Gemmellaro compares his genus with Cyclolobus and says that 

 Waagenoceras differs from this genus because it has six lobes instead 

 of fifteen ; that it has no adventive lobes and that the siphonal lobe is 

 narrowed at the base and has curved branches ; and that the internal 

 varices are straight instead of falciform. 



Alojsisovics^ tried to show that Waagenoceras cannot be separated 

 from Cyclolobus, but Gemmellaro did not accept this view. He tried 

 to show in an appendix to his works, that the two genera are very 

 different from each other. 



'Gemmellaro, Calc. c. Fusulina, p. 9, ibid., App., p. 5. 

 =Mcjsisovics, Arkt. Trias-Amm., p. 18. 



