Geol.-Voi.. II.] ANDERSON— CRETACEOUS DEPOSITS. II3 



smooth on body-chamber, coiled portion crossed by many transverse costae; 

 ventral shoulders of body-whorl ornamented by small, oblique tubercules; 

 dorsal edge of body-chamber expanded over the umbilicus. 



Length of shell, 2 cm.; width, 1.5 cm.; greatest thickness, .6 cm. Septation 

 unknown. 



This shell is apparently related to the preceding, 

 though it has not the characteristic constrictions of that 

 species, and is more flattened on the sides. 



Occurrence. — Found with the preceding in the Lower 

 Chico beds of the Forty-nine Mine, near Phoenix, Oregon. 



The type of this species is in the collections of the 

 California Academy of Sciences. 



59. Scaphites inermis, sp. nov. 



Plate III, Figs. 74-77. 



Shell small, compressed, elliptical in outline, smooth, and almost without 

 ornamentation. Umbilicus open and wholly uncovered; whorls litde invo- 

 lute, ne\^er clasping one-half the preceding whorl, and subcircular in section 

 throughout; body-chamber, however, a little deeper than wide though 

 quadrate; squared or truncated on the dorsal side. The sides of the body- 

 chamber are obliquely crossed by faint transverse, and apparently bifurcating 

 ribs, which continue uninterrupted across the ventral surface. On both the 

 umbilical and ventral shoulders of the body-whorl there are small linear 

 nodes that are almost obsolete on some specimens and hardly appear at all 

 upon the coiled portion of the shell; aperture having a ridge-like rim, hardly 

 a lip, surrounding it, behind which is a shallow constriction, both of which 

 curve backwards at the inner angle of the whorl. On each side of the aperture 

 a small auricular expansion extends forward from near the dorsal edge of the 

 mouth, forming a small triangular surface showing faint concentric strise. 



It is thought worth while to note that upon one specimen, 

 which was accidentally broken, the "impressed zone" of 

 the body-chamber was well exposed. Although the body- 

 volution was entirely free from the earlier coil, this dorsal 

 zone, which had appeared to be squared or truncated, yet 

 contained, as far as the margin of the aperture, a shallow, 

 though distinct groove. 



Occiirrencc. — This species is abundant at the Smith 

 ranch, and has been found also at the Forty-nine Mine, 

 near Phoenix, Oregon. 



