OF CONCHOLOGY. 243 



thinner and smaller. It appears to me to be only a very marked, 

 and probably individual, variation. It may, however, eventually 

 prove coiispecific with " Patella"' Lamanonii, Schrenck, (Amurl. 

 moll.) which is with little doubt the same as '■'■ Patella ' pallida, 

 ■Gld. (Proc. Bost. Soc. Nat. Hist. 1859.) 



This species lives below low water mark, on stones ; it ranges 

 from the Aleutian Islands to San Diego, California. It is very 

 abundant where Eschscholtz procured it, at Sitka, and equally 

 so at Monterey. It is generally overgrown with nullipore which 

 covers it Avith a regular series of nodules, and tinges the shell 

 green or pink. Frequently a tuft of calcareous algae waves from 

 the apex, and the unconscious limpet literally bears a " feather 

 in his cap." It feeds principally upon nullipore, and the en- 

 crusted variety seems to have constituted Eschscholtz' second 

 species of Acmwa {^A. 7nammilla.ta.) 



His first species is the one under consideration, and even if 

 congeneric the name Scurria would have to make way for that 

 of Acma'a, as the latter has eighteen years priority, and this 

 species is the type *, including as it does the first three nomi- 

 nal species of Eschscholtz. Gray (1847) appears to have taken 

 A. scutum {== patina) as the type, because on the plate the fig- 

 ure of scutum, is numbered " 1" ; but it is really the sixth species 

 of the list. The peculiar form and arrangement of the teeth, 

 and the mouth-tubercles separate it from the rest of the Acmseids 

 except, curiously enough, the type of the quondam genus Tectu- 

 ra, which is thus rendered an exact synonym of Aemcea. A 

 pretty full account of the anatomy is given by Rathke, who pub- 

 lished the last portion of Eschscholtz' Atlas, after the death of 

 the latter naturalist. 



ACM^A VIRGINEA, Mlill. sp. Plate 14, fig. 2. 



Patella virginea, Mlill., Prod. p. 237, Zool. Dan. pi. 12, f. 4, 5. 

 Patella parva, Da Costa, Brit. Conch, p. 7, pi. 8, f. 11. 

 Patella pulchella, Fbs., Mag. Nat. Hist, viii, p. 591, f. 61. 

 Lottia pulchella, Brown 111. Conch. Gt. Brit, ii, p. 480. 

 Tectura virginea, S. Wood, Crag. Moll, i, p. 161. 

 Aemcea virginea, Hanley, Brit. Marine Conch, p. xxxii. Fbs. 



and Hani. Br. Moll. ii. p. 487. 

 Tectura virginea, Jefi"r., Brit. Conch, iii, p. 248. 



Soft parts mostly whitish, faintly suffused with pink ; mantle 

 edge thickened, fringed with unequal filaments a little within the 



*This is the only species mentioned by Rathke in the generic diagno 

 sis, and it was also adopted by Philippias the type, in his review of the 

 west coast limpets, in 1846. 



