MAZATLAN UNIVALVES 209 



= A. scutum D'Orb. loc. cit. pi. 64, f. 810, excl. diagn. (teste 



Mid.) 



? = Lottia punctata, Gray ; (non Quoy fy G-aim.) teste Mid. 

 = P. Oregona, Nutt. in Jay's Cat. no. 2852: Jtve. Concfi. Ic. 



pi. 36, f. 112, a, b. 

 + P. umbonata, Nutt. loc. cit. no. 2887 :Rve. loc. cit. pi. 35, 



f. 107, ab. 

 + P. pileata, Nutt. loc. cit. no. 2861. 



This species is known by its comparatively small size, com- 

 pressed sides, and recurved apex. The front part is sometimes 

 covered with stout, rounded ribs, sometimes with a very few 

 fine and separate ones, and sometimes nearly smooth. It is 

 either uniform in tint, or is minutely spotted outside ; inside 

 white and blackish brown. The solitary Mazatlan specimen 

 has broad, rounded ribs, and a somewhat shagreened surface ; 

 and measures long. '96, lat. "8, alt. '42. 



/Za&. Sitcha, Esclisclioltz . Mouth of Columbia Eiver, Nut- 

 tall. Sta Barbara, Col. Jeivett. San Diego, Lieut. Green. 

 Mazatlau ; 1 fresh sp. ; L'pool Col. 

 Tablet 1008 contains the specimen. 



267. ACMJ^A SCABKA, Nutt. 



Jays Cat. no. 2907. .R-w?. Conch. Ic. sp. 119, pi. 37, f. 119, a, b. 

 TsTon Patella (Lottia) scabra Gould Exp. Shells, p. 10 : 



= Patella spectrum, Nutt. in Jay's Cat. no. 2877 : Rve. loc. 



cit. pi. 29, f. 76, a, b. 



Although the name of Gould was published with description 

 before that of Nuttall, yet I have presumed upon the known 

 courtesy of Dr. Gould, in order to avoid re-naming a species 

 which has been widely distributed in collections, and which 

 (as well as Dr. Gould's A. scabra, under the name of P. spec- 

 trum) has been figured in the Conch. Ic. This shell occurred un- 

 named in Dr. Gould's collections. It frequents the temperate 

 portion of the coast, and is easily recognized by its light flesh 

 colour, and tubercular rasp-like surface. Long. 1'06, lat. "9, 

 alt. -4. 

 ffab. California, Nuttall. Monterey and Sta Barbara, Col. 



Jewett Mazatlan ; 1 sp. only ; L'pool Col.$. W. Mexico ; 



1 sp. P. P. C. 



Tablet 1009 contains the specimen. 



