5fi4 REPORT 1863. 



11. Modiola capax, Conr. Galapagos, Cumin g. [Lower] California, Nuttall. 



Mazatlan, Carpenter. [Reigen is the authority for the shells described 



in the Maz. Cat., not Cpr.] 

 17. Modiola Braziliensis, Chera. " Brazil." [At f. 31, which appears the true 



Brazilian shell, we are informed that this specimen is a " variety from 



Guayaquil."] 

 .. Modiola nitens, " Cpr. Cat. Reigen Col. Brit. Mus. California." [The shell 



was erroneously described as from " California " in P. Z. S., and does iiot 



appear in the Reigen Mazatlan Cat. : M. subpurpiireus, Mus. Cum.] 



5. Lithodomus cinnamominus, Chem. Philippine Is. and St. Thomas, W.I. \_ = L. 



cinnamomcuSj Maz. Cat. 177. Probably an Adula.~\ 



8. Lithodomus Ciimingianus, Dkr., MS. "North Australia and Mazatlan.'' [The 



species is figured from the Mazatlan specimen, which may probably be 

 the adult form of L. calyculatus, Cpr.* The cup is not 'distinct, ' but 

 shows a tendency to the peculiar formation described in Maz. Cat. no. 174. 

 Rve.'s diagnosis, however, appears written from Dkr.'s Australian speci- 

 mens, so labelled in Mus. Guru. a very distinct species, without incrus- 

 tations. The name was given by Mr. Coming to a large Chilian species 

 brought by the U. S. Expl. Exp.] 



12. Lithodomus Gruneri, Phil. MS. in Mus. Cum. "N. Zealand." [The species 



=L. falcatus, Gld., and is certainly from California, where it is found in 

 the rocks with Pholadidea penitaJ] 



13. Lithodomus teres, Phil. "Mazatlan." [The specimens in Mus. Cum. are 



labelled " Cagayan, Phil-."~\ 



14. Lithodomus coarctata, Dkr. Galapagos, Cuming. \_=Crcnt>lla c.,Maz. Cat. 17".] 

 16. Lithodomus caudigerus, Lain. "West Indies" [without authority]. "The 



calcareous incrustation produced beyond the ant. extremity is no specific 

 characteristic." [Vide reasons for contrary opinion, Maz. Cat. no. 176: 

 L. aristatus. Dr. Stimpson has seen Lithophagus arranging its peculiar 

 incrustation with its foot.] 



24. Lithodomus pessulatus, Rve. (Oct. 1857). Hab. ? [The unique sp. figured is 

 labelled " Mazatlan " in Mus. Cum. It resembles plumula, with ventral 

 transverse rugae.] 



26. Lithodomus subida, Rve. Hob. ? [=Z. plumula, var.J 



6. Avicula Cumingii, Rve., March 1857. "Ld. Hood's Is., Pacific Ocean, 



attached to rocks, 10 fms., Cuming" \?=zMargaritiphora fimbriata, 

 Dkr., var.] 



9. Avicula barbala, Rve. Panama, under stones at low water, Cuminy. \_ = M. 



fimbriata, l)kr., = 3/. Mazatlanica, Hani.] "Diners from Cuming ii in 

 regular sequence of scales, developed only at margin, and yellowish tone 

 of colour." 



67. Avicula heteroptera, Lam. N. Holland. " A. sterna, Gld." [Gould's species 

 is from Gulf Cal. ; but in Mus. Cum. it is marked inside " semisugitta.'''~\ 

 4. Placunanomia foliata, Brod. Is. Muerte, Bay Guayaquil. " May = ec/i^ato, 

 W. I., but has very much larger orifice." 



7. Placunanomia macroschisma, Desh. "Onalaska, Owning" [who never was 



there]. Kamtschatka, Desh. [Vancouver district, abundant.] 

 7. Thracia pltcata, Desh. "Mr. Cuming has specimens from California and St. 



Thomas, W. I." [Cape St. Lucas, Xantus.~] 

 Melania. [Various species are described from " Central America," &c., which 



or supposed, are rejected altogether. Thus shells sent to Mr. Cuming, with authentic 

 name and locality attached, may appear soon after without any, or with erroneous, 

 quotation. The error is rendered graver by appearing with the weighty authority of 

 " Mus. Cum." 



* The species described in the Brit. Mus. Cat. seldom appear in the monographs, 

 unless there happen to b3 a specimen in Mus. Cum. Soms of the monographers often 

 content themselves with figuring the shells that come most easily to hand ; and do not 

 eem to consider it a part of their work to pass judgment on previously described 

 species, or to concern themselves with what are small or difficult. 



50 



