CALLIOSTOMA. 



361 



III Shell generally swollen or biangular at periphery, spiral strise 

 and lirulse fine, more numerous, closely sharply beaded, group of C. 

 lima Phil. 



Species of the last group are also found in the Gulf of Mexico and 

 on the east coast of South America, having the same distribution 

 that Chlorostoma (plus Omphalius) has. 



( Group of C. canaliculatum MartynJ) 

 C. CANALICULATUM Martyn. PI. 67, fig. 49 ; Vol. X, pi. 41, fig. 34. 



Conical with flat base, thin, light fawn colored with yellowish- 

 white line ; imperforate ; surface of the whorls encircled by numerous 

 sharply sculptured smooth narrow, cord-like lirse, subequal or alter- 

 nately smaller; base with 11 to 13 similar ones. On the upper 

 whorls the line are fewer, and in well preserved individuals the 

 second whorl is minutely beaded above. Spire conic, with nearly 

 straight outlines ; sutures impressed. Whorls 7-8, the last obtusely 

 angular, flat beneath and impressed around the axis. Aperture 

 oblique, rhombic, iridescent and sulcated inside ; peristome thin, 

 acute; columella straightened, not truncate below, dilated in a pearly 

 iridescent pad above, bounded by an opaque white deposit. 



Alt. 33, diam. 33 mill. 



Sitka to San Diego, Cal. 



Trochus canaliculatus MARTYN, Universal Conchologist, t. 32. 

 Tr. doliarius CHEMNITZ, Conchyl. Cab. x, p. 228, t. 165, f. 1579, 

 1580. PHILIPPI, Conchyl. Cab., p. 11, t. 3, f. 1, 2. FISCHER, Coq. 

 Viv., p. 71, 1. 16, f. 1. Ziziphinus canaliculatus Mart., REEVE, Conch. 

 Icon., f. 18. Calliostoma canaliculatum Mart, of American authors. 

 (/) Trochus decarinatus PERRY, Conchology, pi. 47, f. 2. 



In the case of this species, as in other similar cases, I have 

 preferred Martyn's name to that of Chemnitz. Of course, as 

 Fischer says (Coquilles vivantes, Trochus, p. 72), Martyn's work is 

 simply an iconography, without descriptions ; but the great beauty 

 and accuracy of the figures renders identification easy and certain, 

 and these^ qualities should surely receive the same recognition at our 

 hands that we give to a three-line diagnosis, such as most early 

 authors have given us. The principal objection to the work is the 

 rarity of the original edition an objection which applies equally to 

 many early authors whose species are universally accepted. 



Specimens from Vancouver are much smaller than southern shells, 

 and have fewer spiral lirse, the alternate smaller ones being lost ; the 



