SYKES : MOLLUSCA OF " POECUPINE " EXPEDITIONS. 179 



variation, and whether they be adult or not, that I deem it wiser not 

 to describe them. 



Pleurotomella callembryon (Dautzenberg & Fischer). 

 Pleurotoma callemlryon, Dautz. & Fischer : Mem. Soc. Zool. France, 

 vol. ix, p. 428, pi. XV, fig. 15. 



"Porcupine" Expedition, 1870, Station 17. 



Distribution. — Off the Azores, in deep water. 



Mr. Marshall separated four diverse forms, which M. Dautzenberg 

 considers to be all variations of this species. . They certainly show 

 considerable variation, and may eventually prove to be worthj^ of 

 distinct names, but so little is known of these deep-sea forms that, 

 for the present, I have left them under this denomination. 



Pleurotomella ccelorhaphe (Dautzenberg & Fischer). 

 Plexirotoma ccelorhaphe, Dautz. & Fischer : Mem. Soc. Zool. France, 

 vol. ix, p. 425, pi. XV, fig. 13. 

 "Porcupine" Expedition, 1870, Section 17. 

 Distribution. — Ofi^ the Azores, in deep water. 

 Identified by M. Dautzenberg. 



Pleurotomella Dalmasi (Dautzenberg & Fischer). 

 Pleurotoma Dalmasi, Dautz. & Fischer : Mem. Soc. Zool. France, vol. x 

 (1897), p. 153, pi. iii, fig. 4. 

 "Porcupine" Expedition, 1870, Station 17. 



Distribution. — Previously recorded from deep water off the Azores. 

 Pleurotomella eurybrocha (Dautzenberg & Fischer). 

 Pleurotoma eurybrocha, Dautz. & Fischer : Mem. Soc. Zool. France, 

 vol. ix, p. 427, pi. XV, fig. 13. 

 "Porcupine" Expedition, 1870, Station 17. 

 Distribution. — Off the Azores, in deep water. 

 Identified by M. Dautzenberg. 



Pleurotomella Formosa (Jeffreys). 

 Defrancia formosa, Jeffreys: Proc. Zool. Soc, 1883, p. 397, pi. xliv, 



fig. 9. 

 Pleurotomella Packardi, vav. formosa, Jeff. : Kobelt, p. 282. 



"Porcupine" Expedition, 1869, Stations 14, 23«, 65; 1870, 

 Station 17. 



Di.4ribution. — Deep water in the Atlantic, south to Azores (?) ; also 

 if it be a variety of P. Pachardi, on the American coast. 



The following notes are due to Mr. Marshall: "There is some 

 confusion as to the identity of this species. Jeffi-eys in his description 

 says that the 'apical or top whorls are reticulated,' and that the 

 ' point is usually sharp, but sometimes blunt and button-shaped,' 

 although his figure of the shell, as well as the magnified view of the 

 apex, does not exhibit any reticulation. The Rev. R. Boog Watson 

 (Challenger Gasterop., p. 350) demurs to this part of Jeffreys' 

 description, and says he has ' seen nothing like such a variety of 

 form [of the apex] in any specimens of this species, nor in any shells 

 of the whole Clathurella group.' He describes the embryonic section 



