10 U.S. NATIONAL MUSEUM BULLETIN 291 



bearing 1 to 2 suckers, the long, slender tentacles with iinexpanded 

 clubs bearing numerous minute suckers, and the ^^Om^rmstrephes-Vike'^ 

 anterior section of the gladius. 



The specific description is an amplification of the generic diagnosis, 

 Hoyle gave the following details : arm formula 4.3.2.1 ; arms only one- 

 fourth as long as the body ; delicate protective membranes on the arms; 

 suckers spheroidal, nearly embedded, sucker rings smooth wnth 2-3 

 rows of conical papillae ; hectocotylus lacking; club one-eighth as long 

 as tentacle; club sucker rings smooth with two rows of papillae. 

 Hoyle's accompanying illustration (fig. 2, p. 309) indicates that the 

 specimen had undergone distortion during capture and preservation ; 

 this may account largely for the discrepancies in shape and proportion 

 of fins, head, mantle, and arms noted by later authors, particularly 

 Chun (1910) andPfeffer (1912). 



Hoyle's comprehensive report on the ChalUnger cephalopods ap- 

 peared in 1886. The first section of this work is a synoptic listing of the 

 recent cephalopods. The genus Bathyteuth'ts Hoyle, 1885, is listed under 

 the family Ommastrephini Steenstrup, 1861, subfamily Ommastre- 

 phidae Gill, 1871, with Benfhoteuthls Verrill, 1885, as its synonym. 

 Hoyle listed two species in this genus : his own B athyteutkis ahyssicola 

 and Verrill's B. megalofii. Hoyle mentioned in the discussion the pos- 

 sibility that the two species might ultimately prove to be conspecific 

 (p. 169) ; in the zoogeographic and bathy metric sections of this mono- 

 graph, however, he continued to list them separately. 



Hoyle, in an attempt to delimit the distributions of cephalopods, 

 defined four major zoogeographic regions of the oceans and seven 

 bathy metric zones between the surface and 3000 fathoms (5500 m). 5. 

 megalops occurred in the Atlantic Ocean region, 60O-1073 fathoms 

 (1100-1950 m) ; B. ahysHicola inhabited the Indian and Southern 

 Ocean regions at 1600 fathoms (2925 m) . 



In his discussion of bathymetric distribution, Hoyle stated that 

 there is reason to regard Bathy teuthis and Benthoteuthls (which "ob- 

 viously belongs to the same genus" [p. 232] ) as deep-sea inhabitants. 

 Hoyle drew attention to Verrill's observation of embryonic characters 

 in this genus, but he considered these as characters that indicate a 

 deep-sea habitat. In addition, he believed that the small fins were ill- 

 adapted for pelagic existence, that the minute suckers were not fitted 

 for raptorial purposes, and that the large buccal membrane was well 

 suited for collecting food from an oozy bottom. 



The generic diagnosis and the specific description are nearly "verba- 

 tim" duplications of those given in his preliminary report (Hoyle, 

 1885b) with the exception of two phrases. In the earlier work he stated 

 it was impossible to determine if the gladius formed a terminal conus, 



