—a 
ON MOLLUSCA OF THE WEST COAST OF NORTIT AMERICA. 545 
189. Area senilis is from W. Africa (not “1. Indies”): one of the many representative 
species between the two West Coasts. 
185. Noétia reversa, Gray. 
186. Argina brevifrons, Shy. 
188. This is the young of Barbatia alternata. 
191-195 belong to the group Barbatia. 
195. = Barbatia Tubogensis, from type. 
203. The young of this shell is Aricula libella, Rve. Dy. Gould protests against 
some of the interpretations here given to his views. 
204. The W. American pearl-oyster should stand as MZ. fimbriuta, Dkr. It has 
been redescribed as AZ. barbata, Rve. 
212. Dr. Gould protests against the Pacific shells being regarded as O. Virginica. 
Mr. Hanley adheres to his original opinion. Fossils seut from the Sand- 
wich Is. by Mr. Pease (O. Sandiichensis, Pse.) appear scarcely to differ. 
214b. The O. palmu'a appears a distinct species. 
215. This species is identical with O. no. 384 of C. B. Ad. It may take the name 
of O. amara from its “ bitter flavour.” 
224, Bulla Adamsi=B. punctulata, C. B. Ad., non A. Ad. 
229. Haminea eymbiformis is closely allied to ZH. virescens, Sby. 
239, Siphonaria lecanium. S. maura, Sby., is one of the varieties of this species. 
The S. palmata may prove distinct. S. ferruginea, Rve., is probably de- 
scribed from the intermediate form. 
242, Lunthina striulata, Name given in ignorance of sfrivlata, Ad. and Rye. ; and 
not needed, teste Rve. 
245, The Dentalium hyalinum of Phil. is probably the young ‘of D. semipolitum : 
this species is distinct. 
247. The Dent. pretiosum of Nutt. is a northern species ; this is most likely D, lac- 
teum, Phil. 
248-250, This typical group of Chitonids retains the Linnean name in Dr. Gray’s 
arrangement; and as he first pointed out the generic distinctions in the 
family, his judgment is to be preferred. 
252-254, 256. These species belong to Ischnochiton, Gray. 
255, Lepidopleurus, Risso, has sculptured valves and scaly margin, and is probably 
synonymous with Lophyrus, H. and A. Ad. The name may be retained for 
the “ Lophyroid ” Zschnochiton here described, the peculiarities of which haye 
been confirmed by adult specimens in Mus. Cuming, and by other species. 
257. Chiton, H. and A. Ad.,=Acanthoplewra (Guild.), Gray. 
262. = Nacella peltoides, n. s. (described from Cape St. Lucas specimens). 
263. The true Lottia pintadina of Gld. (teste figured types) consists entirely of 
varieties of A. patina. 
265. The “ large flat shell” referred-to is Tecturella grandis, Gray, Brit. Assoe. Rep. 
1861, p. 187. Tecturella is preoccupied by Stimps. Gr. Manan Invert. — [t 
being needful to divide the old genus demea, Lottia may be used for this 
section. By reviving synonyms as sectional names, when a genus is divided, 
good names may be retained in a restricted sense, and the burden of a spu- 
rious nomenclature lessened. The species is Lottia gigantea (Sby. Gen.). 
269, Scutellina navicelloides, Cpr.,= Crepidula osculans, C. B. Ad. 
280, This should stand as Gadinia stellata, Shy., that name having been given to 
the normal form, Rep. pl. 7. f. 3a, of which pentegoniostoma, f. 3f, is only 
an accidental variety. 
282. Callopoma Fokkesii=tessellatum, Rye., is the Lower Californian form, and 
probably distinct. 
2830. = Turbo phasianella, C. B. Ad., non Melaraphe phasianclla, Phil. 
289. The first name is T. eximius, Rve., P.Z. S. 1842, p.185; Mke.’s shell bearing 
date 1850. It appears identical with “ Javaniews, Lam.,” in Mus. Cum., and 
is extremely like “ spectosus, Japan.” Trochus heing now generally retained 
for the Miloticus group, which contains the largest forms, it is best to revive 
Swainson’s excellent name Calliostoma for the “ Ziziphinus ’evoup. A specific 
name should not be used for a genus, where a distinctive name has already 
been accurately described, 
1863, 2 
