MUSEUM OF COMPARATIVE ZOOLOGY. 225 



Genus TRITONIUM Link. 



Tritonium Bolten, Mus. Bolt., p. 125, 1798; ed. ii. p. 88, 1819. (No descr.) 

 Tritonium Link, Beschr. Rostock Samml., p. 121, May, 1807. First species, Murex 



tritonis Linne. 

 Tritonium Cuvier, Regne Anim., II. p. 440, 1817. First species, Murex tritonis Linne'. 

 Triton Montfort, Concliyl., II. p. 487, 1810; not of Linne, 1768 (Crust.), nor of 



Laurenti, 1768 (Batrachia). 

 Not Tritonium O. F. Miiller, Prodr. Zool. Dan., p. 243, 1776. 



The genus Tritonium of 0. F. Miiller was not a separation of incongruous 

 material from a heterogeneous assembly and its discrimination apart, but the 

 compounding out of genera already existing of a new heterogeneous combina- 

 tion about equivalent to the Pectinibrancldata as now understood. It fell 

 deservedly, and the name was left unemployed. Though the second use of such 

 names is not to be commended, and is by common consent at present aban- 

 doned, it would create immense confusion and difficulty if one were to apply 

 such an ex post facto law impartially to the older writers. There is no good 

 reason why we should not adopt the name proposed by Bolten, given a scien- 

 tific standing by Link, and adopted by Cuvier. 



The original group has been considerably divided; in fact, Bolten, Mont- 

 fort, and others began the work of division. The whole matter is worth an 

 exhaustive discussion for which the present paper does not afford the most 

 appropriate opportunity. 



Tritonium tritonis L. var. nobilis Conrad is found in this region, but was 

 not collected by the Blake. 



Subgenus COLUBRARIA Schumacher. 



Colubraria Schurn., Essai, p. 251, 1817. Fischer, Man., p. 654. Type, Tritonium 



maculosum Gmel. 

 Epidromus Morch, Cat. Yoldi, p. 107, 1852. 

 Cumia Bivona-Bernardi, Nuovo Gen., 1838. Type, Tritonium lanceolatum Menke. 



Colubraria lanceolata Menke. 



Ranella lanceolata Menke, Synopsis, ed. i., p. 87, 1828 (excl. syn.). Morch, Malak. 

 Blatt., XXIV. p. 25, 1877. 



Habitat. Off Sombrero, in 54 fms. Station 2596, of the TJ. S. Fish Com- 

 mission, 17 miles E. S. E. from Cape Hatteras, N. C, in 49 fms., sand, bottom 

 temperature 75°.0 F. Bahamas, Rawson; Antilles, Morch ; Vera Cruz, Mexico, 

 Strebel. 



VOL. xviii. 15 



