^"ik!k'^''] lMiOCKKI)IN(;lS OK Till': NATIONAL MUSEUM. 371 



These valves evidently beloiift- to a species tliat iiiliabits tlie littoral 

 zone, and to examjdes tliat inhabit tlie n])])<'r belt of said zon<'., and 

 j'asten npon small stones or to the roots ol" manj^roves oi' some other 

 shore-inhabitinft' shrnb. Of the many si)e(;i('s that have been described 

 from the west coast quite likely one-half are synonyms. 



The form of individual examples, as well as of tlie several iinlivid 

 uals that (constitute a colony, is so (lej)endent upon the object to which 

 the individufil or tlie mass is attached, that a satisfactory diagnosis is 

 out of the (juestion with anything- less than a larj;e series and a mal- 

 titude of specimens. 



Wimnwr credits oiu; of (lould's species, (>. (/I(>mrr((f<t {vide Reeve's 

 Mono<iraph (Jonch., Icon., Fi<;s. 52, a, b, c, d), to the ( Jalai)a^os, but 

 liceve makes no leference to any s))ecies of oyster in these islands, and 

 it may therefore be assumed that in the (Jumin^ian collection these 

 islands were not reprc^sented. O. (/I(>nier<il<( is, for an (htrea, a lather 

 well-characteri/ed species, an<l Iteeve's li;j;nres are in this instance par- 

 ti(;ular]y good, so that it may be assumed that Wimmer's determina- 

 tion, if made from dire(!t com]»arison with Iveeve, is most likely correct; 

 nevertheless I am disi)os('d to doubt the presence^ of f/lomcnita in the 

 Gahipagos until contirmed by further testimony or additional material. 

 0. glomerata is rather an Indo-Pacitic; form, (^xtemling northerly and 

 westerly to the islands of Japan. It is probable that (lould's niordd.v, 

 collected by (" Wilson's lOxju'ditiiur' in Ueeve, in enor for) Wilkes's 

 Expedition, and doubtfully assigiu'd to California, is really a West Coast 

 form; by some authors it has been regarded as a synonym of '■^ (jlom- 

 erata.^^ I can conceive of varieties of tnordau; closely approaching 

 ^^ glumcratOj" but in general features only. 



Family ANOMIID/K. 



fiwiHiH Anomia lAnn6. 

 2. Anomia adamus Gray. 

 =A. Lnm])f (<riiy, a iuiety. 



One left valve, b<^a('.ll, in j^ood conditJon. 



James Island. 



Of the nunwrous alleg<'(l si)e(;ies tigui-ed in Jlecne, A. admnns is the 

 oidy one credited to the (Jalaitagos, where (Juming obtained theexam- 

 l>le described by Dr. (irray near Lord Hood's Island, at the dejilli of 

 i'athoms, attached io '■'• Avicula mar<i<iritlj'era.'''' If the desctription had 

 been without the habitat, I should have recorded the specimen herein 

 listed under tin; name of A. laitrpr, the latter being familiar to col- 

 lectors generally, and usually attached to the s|)ecies in collections. 



In the Proceedings of the Zoological Society of London for the year 

 1849, Dr. J. E. CJ ray described (pp. 110, 117) seven species from the 

 west coast of th«^ Americas, including the tbiegoing, to wit: Jidenas; 

 paciliis, 'larhn.s, aleciiis, and hamilhis. Dr. Carpenter, in his Check- 



