A. E. Verrill — North American Cephalopods. 251 



Sessile arms with hooks only. 



Verania. — Tentacular-club with suckers only ; sessile arms with 

 hooks only. 



Acanthoteuthis. — Tentacular and sessile arms with hooks (fossil). 



Ancistrocheirus. — Tentacular and sessile arms with hooks in two 

 rows. Pen dilated at both ends. 



Enoploteuthis (typical). — Tentacular-clnb with two rows of hooks, 

 and with a cluster of small suckers on the wrist. Sessile arms all 

 with hooks in two rows, extending to the tips. 



It will be evident from these characters, that Mr. Dall's species, 

 having two rows of smooth suckers, at least on the basal portion of 

 the ventral arms, can belong to none of these genera, except those in 

 the first group and Lestoteuthis in the second. Of these, Gonatus 

 would be excluded from consideration by its diflferent pen and four 

 rows of suckers; Onychia and typical Onychoteuthis by the form of 

 the pen. After this elimination we still find three geneiic groups to 

 either of which it might belong, so far as its armature is known, viz : 

 Ancistroteuthis, Dosidicus, and Lestoteuthis. The first of these is, 

 perhaps, nothing more than a sub-genus of Onychoteuthis, the princi- 

 pal difterence being in the pen, which is somewhat pennate and 

 lanceolate in the typical species of the latter, but nearly linear with 

 a solid cartilaginous terminal cone in the former. In this last char- 

 acter, and in the general form of the pen, O. robusta somewhat 

 approaches A. Tiichtensteinii. But Dosidicus and Lestoteuthis also 

 have a solid cartilaginous cone, and the latter, especially, agrees 

 most closely in the general form of the body and caudal fin ; and its 

 pen has very nearly the form and structure seen in 0. rohusta. 



So far as we can ju^dge, therefore, with our present imperfect data, 

 the relationship of 0. robusta appears to be rather with Lestoteuthis 

 than with any other known group. It is possible, however, that its 

 afiinities may prove to be closer to Ancistroteuthis, when the arma- 

 ture is discovered. 



Lestoteuthis, gen. nov. 

 The characters of Lestoteuthis ICamschatica, which I propose to 

 take as the type of this generic group, are not yet fully known. The 

 peculiarities in the armature, both of the sessile and tentacular-arms, 

 as given above (p. 250) are quite sufiicient, however, to warrant its 

 sej)aration from all the other genera. Its pen, as figured, also differs 

 from all others, hitherto described. It is narrowest anteriorly, 

 gradually and slightly expanding backward to the one-sided conical 



