Geol.— Vol. II. ] ANDERSON— CRETACEOUS DEPOSITS. 87 



26. Lytoceras (Gabbioceras) angulatum, sp. nov. 



Plate VI, Fig. 139. 



Ammo7iites batesi (pars.) Gabb, Pal. Cal., Vol. II, p. 132, Pis. XX and XXI, 



figs. 9 and 10, 1863. 

 Gabbioceras batesi Hyatt, Phylogeny of an Acquired Characteristic. 



One of the species which was believed by Gabb to be 

 only a variety of Ammonites batesi has below the diameter 

 of 3.8 cm. a strongly angular section. There are few who 

 will maintain the identity of these species even upon an 

 inspection of Gabb's figures. 



In the collections of the Universit}'' of California are three 

 well preserved examples of this shell, from which the draw- 

 ing (fig. 139) was made. One of the specimens has the 

 aperture complete, though crushed. It has been restored 

 in the figure. The shell does not apparently attain a large 

 size. Two of the specimens seem to be mature and are 

 less than three inches in diameter. 



The involution of the shell is considerably greater than 

 either of the preceding species which Gabb included under 

 the name Ammonites batesi. The body-chamber, which in 

 these specimens occupies almost a complete whorl, is crossed 

 superficially by a few moderately strong, transverse, sinuous 

 grooves not evenly distributed. The shell between these is 

 polished, though marked with a few fine lines which bend 

 gently backward within the umbilicus. 



The shell increases rapidly in size after losing its angular 

 character at a diameter of one inch or less. 



Occurrence. — The stratigraphical position of this species 

 can not be given with certaint}'. The specimens are all 

 labeled " Cottonwood Creek, Shasta County." They are 

 probabl}" from the Horsetown beds of that region. 



27. Hamites ellipticus, sp. nov. 



Plate III, Figs. 102-103; Plate X, Fig. 191. 



Shell compressed, elliptical in section, more narrowly rounded upon the 

 ventral or siphonal side than upon the dorsal; surface ornamented with sim- 

 ple and narrow transverse ribs separated by wider, rounded grooves; no 



