MUSEUM OF COMPARATIVE ZOOLOGY. 61 



spects is well known, and extends from the margin of the sea and land to va- 

 rious depths according to the local temperature, but rarely in a living condition 

 below 2i)0 fathoms. Dead specimens belonging to this region, disgorged by- 

 birds or fishes, or washed by currents, are found mixed with the true deep- 

 water fauna, and require the exercise of caution in assigning to the latter its 

 true members. Thus, for instance, I find a specimen of Pupa, a land-shell, in 

 dredgings from over 800 fathoms. The specimens from great depths off Morro 

 Light, Havana, Cuba, are particularly mixed with littoral material. 



"III. Lastly, we have the true deep-sea species, ranging from 1,920 fathoms 

 to 200 fathoms, according to temperature, many of them coming much nearer 

 the surface, when the temperature is cool enough, than has commonly been 

 taken for granted. 



" The material from regions I. and II. does not call for any especial remark 

 at this time, but appears to contain some new forms, among them Calliostoma 

 Psyche, a beautiful new species of Trochoid shell, recalling European rather 

 than the West American forms of the genus, and remarkable as being the sec- 

 ond species of the group known to inhabit the Gulf, which is peculiar for the 

 paucity of Trochi. It does not seem to inhabit the shores, but is intermediate 

 between the true deep-sea forms and those of the shore. I find among the 

 members of the third bathyraetrical zone several species known to be widely 

 distributed in the deep-sea, such as Pleuronectia lucida, Jeffreys, and species of 

 Limopsis area, etc. figured, but not named, in Thomson's Atlantic Ocean vol- 

 umes of the " Challenger " voyage. Besides these, the most interesting species 

 are Lyonsia bulla, n. s., which may with further study prove to belong to the 

 fossil genus Gressleyia of Agassiz ; Euciroa elegantissima, n. g. et sp., a beauti- 

 ful pearly bivalve of the exquisite Verticordia group, which are mostly fossils ; 

 Pleurotoma {Candelabrum) cathedralis, n. s., an exquisite gem collected by Pour- 

 tales in the Gulf Stream expedition several years ago, but of which the original 

 specimens were lost in the Chicago fire ; and Dentalium perlongum, n. s., the 

 finest and most delicate of this abundant genus. The genera obtained from 

 depths below 500 fathoms are Limopsis, Area, Aximea, Gouldia, Pleuronectia, 

 Leda, Nueula, Lyonsia, Pleurotoma, Calliostoma, Trochus, Minolia, and Denta- 

 lium, Vjesides dead shells, which may or may not prove to belong with these 

 associates. 



"Of these, those from a greater depth than 1,000 fathoms are Lyonsia bulla, 

 Limopsis, Area, Leda, Gouldia, Dentalium, and a form of Trochus allied to Mi- 

 nolia. The Lyonsia cited came from the greatest depth of any, 1,920 fathoms. 



" The general aspect of these collections is free from any trace of West Amer- 

 ican peculiarities. This was unexpected, remembering the Haliotis dredged 

 off Florida by Pourtales in his earlier work ; but that species was, according to 

 my recollection, more allied to African than West- American forms of the same 

 genus, and might indeed have proved identical with some West- African deep- 

 water species, had its characters been put on record before it disappeared in 

 the Chicago conflagration. 



"I shall send preliminary diagnoses of the few forms specifically named 



