OF CONCIIOI.OGY. 253 



C. asmi^ and none of the specimens alluded to approached the 

 latter in solidity, were as roundly conical, or were^as smooth as 

 the typical ashii. Very perfect specimens of the latter show 

 under a strong magnifier exceedingly fine, close grooves, which 

 are usually invisible to the naked eye, and are different from the 

 sculpture of either pelta or patina. Mr. Stearns found numbers 

 of specimens attached to Chlorostoma funebrale, and it has not 

 been found alive anywhere else. Its range, as far as known, is 

 from Sitka to Santa Barbara Island, and it is rare everywhere, 

 but perhaps most common at Monterey. 



COLLISELLA MITELLA, Mke. sp. Plate 14, fig. 9. 



Aancea mitella, Mke., Zeitschr. f. Mai. 1847, p. 187, No. 43. 

 Patella navicula, Rve., Conch. Ic. pi. 40, f. 130 a, b. 1854. 



The dentition of this species was obtained from a very small 

 dry specimen. Dr. Carpenter describes the shell, (Maz. Cat. 

 p. 210). It has, as far as I am able to discover, been reported 

 only from Mazatlan and the Gulf of California. 



COLLISELLA STRIGATBLLA, Cpr. Sp. Plate 14, fig. 5. 



Acmcea strigatella, Cpr., Ann. and Mag. N. Hist. 3d ser. xiii, 



1864, p. 474. 

 A. sirigillata, Cpr., Sup. Rep. 1863, p. 618, No. 17. 



The dentition of this species was also worked out from a small 

 dry specimen, which afforded no details in regard to the animal. 

 It is reported from Cape St. Lucas, where it was collected by 

 Xantus. 



COLLISELLA FASCICULARIS, Mke. sp. Plate 14, fig. 11. 



Acmcea faseicidaris, Mke., Zeitschr. f. Mai. 1851, p. 38, No. 



134. 

 Patella opea, Rve., 4- A. mutabiUs, Mke. (pars). 



A similar remark will apply to this species. It has been ob- 

 tained from Cape St. Lucas, Margarita Bay, Mazatlan, and the 

 Gulf of California generally. In this species and 0. mitella the 

 specimens from which the teeth were obtained were so very mi- 

 nute that the accessory uncinus could not be clearly made out, 

 and hence is omitted in the figure. An examination of the adult 

 radula would doubtless disclose them, as in the allied species. 



CoLLISELLA PALEACEA, Gld. Sp. 



Aemcea paleacea, Gld., Mex. and Cal. Shells, p. 3, pi. 14, fig. 



5. Cpr., P. Z. S. 1856, No, 40. 

 Some specimens of the animal of this species, which I owe to 



