1914] 



Martin : New Species of Fossil Mollusca 



187 



one-fourth of their width below the suture, cylindrical below angle, 

 ornamented with seven or eight broadly rounded, raised, spiral cords, 

 two of which occur on the tabulation, one at the angle, and four or 

 five in front of the angle; cords on the tabulation and angle very 

 large, separated by deep interspaces which are almost as wide as the 

 cords themselves ; cords smaller on the anterior portion, separated by 

 narrower, grooved interspaces; the tabulation has a stepped appear- 

 ance produced by the cord nearest to the suture being raised above 

 the one just anterior to it ; suture distinct, impressed ; body-whorl 

 large, uniformly tapering below the middle, sharply rounded above, 

 ornamented with twenty-five spiral cords arranged in the same manner 

 the angle ; rugose, axial lines of growth visible over the entire surface 

 of the shell ; aperture ovate ; outer lip defective ; inner lip incrusted ; 

 pillar long, with anterior sulcus ; canal short, curved. 



Dimensions. — Length of type specimen, apex of canal defective, 

 85 mm. ; maximum diameter of the shell, 50 mm. ; length of the aper- 

 ture, 45 mm. 



Occurrence. — The type and fragments of three other specimens 

 were obtained from the Wildcat Series on Eel River near Scotia, 

 Humboldt County, California. University of California Locality 

 1878. 



This species can be distinguished from Ghrysoclomus bairdii Dall, 

 which it most closely resembles, by the more ventricose form, the 

 whorls increasing in size more rapidly, more numerous and more 

 closely set spiral cords, and the presence of two strong spiral cords 

 on the tabulation. 



Named in honor to Mr. F. M. Anderson, curator of invertebrate 

 palaeontology, California Academy of Sciences, San Francisco, Cali- 

 fornia. 



CHKYSODOMUS PURISIMAENSIS, n. sp. 

 Plate 19, figure 2 



Shell thick, elongate, with seven or eight well-rounded, smooth 

 whorls; spire strongly elevated, about one-third the total length of 

 the shell ; whorls of the spire unsculptured, except for the first few 

 which show faint spiral grooving; posterior one-quarter of each whorl 

 concave with well-rounded shoulder one-third of its width from the 

 posterior margin, evenly rounded from the shoulder forward, faint 

 indication of collar just anterior to the suture ; suture appressed, dis- 



