340 PSOCEEDINGS OF UNITED STATES NATIONAL MUSEUM 



north vvtii'd to Finmark. In Asia, according to Schrenck, it reaches Yesso 

 and the Tartarian coast. "Mexico" is quoted, ex B. M. tablet, by Jef- 

 freys; of course due to ballast or some mixture of specimens or labels. 

 North of the Pribiloft' group, in Bering Sea, it ai>pears to be the sole 

 form of the genus. 



C. testudinalis var. patina. 



Acmwa patina Esch. Eathke, 1. c. p. 19, pi. xxiv, f. 7-8, 18.33. 



C. patina var. vormaUs sive pintadina (Gld.) Dall, 1. c. p. 247, pi. 14, f. 4, 1871. 



Tectum patina Martens, 1. c. p. 9.3, pi. 3, f. 7-8, 1872. 



Hah. — Aleutian Islands, eastward and southward on the Alaskan side 

 to San Diego, California. Six fathoms to high- water mark; usually 

 between tides. 



The characters assigned to imtina by most naturalists are those of 

 southern specimens (which were described as Patella pintadina by 

 Gould), nineteen-twentieths of the specimens in museums having come 

 from California. 



In northern waters these distinctions are more or less obsolete, but 

 on a comparison of Californian with Massachusetts Bay specimens it is 

 very easy to draw the line between them, and this holds good for indi- 

 viduals as far as the Aleutians, but not for the generality. 



C. testudinalis var. alveus. 



Hah. — Sitka northward and elsewhere with the typical form in, At- 

 lantic seas, a variety formed the residence of the individual on a narrow 

 frond of seaweed or Zostera. Tectura alveus of authors. 



C. testudinalis var. Cumingii. 



Patella Cumingii Eeeve; DaU, 1. c. p. 248. 

 Hal). — From the Pribilofif Islands southward with var. patina. Com- 

 monest toward Cook's Inlet, rare at the northern extreme of range and 

 south ward of Vancouver Island. Usually near low- water mark, and 

 most frequently in isolated rocks washed by the surf. 



C. testudinalis var. ochracea. 



Dall, 1. c. as var. patinw, p. 249, pi. 17, f. 35. 



Hitherto found chiefly in California, but reported from Vancouver 

 Island by Hepburn; rare. 



My largest specimen of var. patina is two and three-quarters inches 

 long; another is an inch high. Every imaginable fluctuation in color, 

 elevation, smoothness or striation, width in proportion to length, «&c., 

 may be found somewhere in the series before me. Yet, after uniting 

 patina to the older form, there is a certain fades which distinguishes the 

 species from any other with tolerable readiness. It is the commonest 

 of aU the species in Alaska and over the whole northwest coast of 

 America. 



