A. E. Verrill — North American CephalopocU. 



355 



than that above it ; the aperture is small, ovate, with a smooth rim ; 

 their pedicels are short and laterally attached. In the female the 

 corresponding suckers are not only smaller but are differently shaped, 

 the basal portion being smaller than the upper portion. The suckers 

 of the tentacular arms are very numerous, minute, shallow, cup- 

 shaped, with oblicpie rims and slender pedicels; they are neai'ly 

 equal and appear to form eight to twelve rows. 



Young specimens, Avith the mantle less than 12"'"' in length, can 

 scarcely be distinguished sexually by external characters, and are 

 not easily distinguished from the yoUng of Jiossia Hyatti, of 

 similar size. 



One of the original specimens ( $ ) measured, from the base of the 

 arms to the end of the body, 46""" ; length of body, 31 ; of head, 15 ; 

 breadth of body, 22 ; of head, 23 ; length of fins, 20 ; of their insertion, 

 16; breadth of fins, 10; front edge of fin to edge of mantle, 2-5; 

 length of free portion of dorsal arms, 16; of second pair, 17; of third 

 pair, 20; of ventrals, 15; of tentacular arms, 25; breadth of dorsal 

 arms at base, 3 ; of second pair, 3 ; of third, 3-5 ; of ventrals, 3-5 ; 

 of tentacular arms, 3-5; of the terminal portion, 3*75 ; its length, 10 ; 

 diameter of the largest suckers of sessile arms, -8 ; length of free 

 portion of siphon, 7""". 



Measurements of Rossia sublevis and R. Ilyatti. in millimeters. 



Sex ... 

 Station 



Length of mantle, above 



Breadth of mantle 



Breadth across head 



Diameter of ej'es 



Length of a fin 



Length of its base 



Transverse breadth of a fin 



Length to base of dorsal arms*. 

 " " " third pair 



tip 



ventral arms 



dorsal arms 



second pair 



" " •' third pair 



" " " ventral pair 



Length of tentacular club 



Its breadth 



Diameter of largest suckers of lateral arms. 



R.suhlevis. 



879 



29 

 22 

 26 

 16 



21 



n 



14 

 45 

 46 

 41 

 64 

 65 

 66 

 61 

 9 

 2-5 

 2-2 



894 



32 



25 

 30 

 16 

 24 

 19 

 15 

 47 

 47 

 43 

 71 

 75 

 78 

 74 

 15 

 3 

 1.1 



R. Hyattl. 



* The length to the ' bases' of the arms, is from the posterior end of the body to the 

 free edge of the basal web, between the arms ; that of the third pair is to the edge of 

 the web, between the second and third pairs. The measurements are all from well 

 preserved alcoholic specimens. 



Trans. Conn. Acad., Vol. V. 43 June, 1881. 



