126 AMERICAN JOURNAL 



columella arcuate, white ; toothlike process blue. Nucleus of 

 two and a half whorls, flesh-color, with revolving lines. 



Maj. diam. -75 ; min. diam. *61 ; alt. *7 in. ; defl. 85°. 



Habitat. — Guaymas, ten specimens, Dr. E. Palmer. 



This shell does not appear to have been described in any of 

 the works at my disposition. It is nearest to eximium, from 

 which it is readily distinguished by the blue umbilical region and 

 the different coloration of the revolving ribs, which, in eximium, 

 are much less prominent and are mostly colored with alternate 

 purple, black and white instead of brown and white. The color 

 and sculpture differs from that of C. lima, which is granulate on 

 the base and wants the upper carina. I know of no other spe- 

 cies with which it can be well compared. 



Calliostoma costatum, Martyn. 



This species passes through a number of variations, which, 

 however, do not obscure the specific characters. The ribs are 

 usually yellowish, smooth with reddish brown interspaces. The 

 apex is blue when eroded. The whole sometimes has a more or 

 less olivaceous cast. The yellow of the apical ribs is usually 

 interrupted by patches of brown. This is sometimes continued 

 on the lower whorls, when the three ribs nearest the suture and 

 often one or two on the carina, of the whorls are prettily painted 

 with alternate patches of dark brown and greenish white. The 

 ribs are more or less prominent, some specimens having them 

 quite sharp while in others they are hardly raised. In one other 

 exquisite variety the three sutural ribs and their interspaces are 

 of a very rich purple blue, which is not due to erosion. The 

 umbilical rib is sometimes salmon-colored. The nacre is of great 

 brilliancy. Found from Sitka to Santa Barbara and San Diego. 

 Mr. Stearns and myself, after an examination of the type, were 

 disposed to consider 0. splendens, Cpr., as a very young speci- 

 men of the blue painted variety above alluded to. 



Calliostoma canaliculatum, Martyn. 



This is, perhaps, less variable than any other Californian spe- 

 cies. The ribs have a slight tendency to become beaded, and 

 always are more or less so on the apical whorls. The nucleus is 

 heliciform, smooth and whitish-hyaline, comprising a whorl and 

 a half. The ribs of the first three whorls are more or less beaded. 

 Five radiating brown spots are to be seen on the apical whorls, 

 and obsolete, but similar markings may be seen on the others. 

 The apex when eroded is light blue ; the principal variations in 

 color are in the darker or lighter brown of the interspaces. 

 Northern specimens are usually darker and smaller. There is 



