MUSEU.AI OF COMPARATIVE ZOOLOGY. 



109 



two alternating rows ; the free portion is slender, rounded externally, and 

 tapers to a slender tip ; on the distal half, the sucker-pedicels are long, very 

 prominent, conical, larger than the suckers, and tapering toward the tip, which 

 terminates in a minute conical sucker, without any constriction between it and 

 the pedicel ; of these there are ten or more pairs on the lateral and ventral 

 arms, and four or five pairs on the dorsal arms ; the length of the sucker-pedi- 

 cels and suckers together is greater than the diameter of the arins ; on the 

 basal half of the arms the suckers are of the ordinary structure, as in Rossia ; 

 they are small, with small apertures, oblong, obliquely attached, on short, 

 slender pedicels, which are surrounded by submarginal swellings of the arm- 

 surface. Of these normal suckers there are nine to ten pairs on the lateral 

 and ventral arms ; of these two or three, at about the sixth or seventh pair, on 

 the lateral arms, are distinctly larger than those before or beyond them. One 

 or two of intermediate form connect the normal with the specialized suckers. 

 The dorsal arms are united together along their inner surfaces, which turn 

 toward each other, for some distance from the base by a thickened membranous 

 fold, which forms a sort of pocket or sinus between the arms, probably for 

 sexual purposes. Tentacular arms are long, slender, triquetral, tapering dis- 

 tally; club small, curled, a little wider than the portion of the arm just below 

 it, covered with numerous very minute suckers, arranged in many rows. 



Siphon relatively large and prominent, projecting forward in front of the 

 bases of the ventral arms. 



Measurements of Nectoteuth 



Length to tip of longest sessile arm, 

 '' dorsal edge of mantle, 

 " ventral edge of mantle, 

 " bases of lateral arms, 



Breadth of body (or head), . 



Diameter of eyeball. 



Longitudinal extent of fm, . 



Breadth from base to outer edge, 



Length of its insertion, 

 " dorsal arms, 

 " second pair, . 

 " third pair, 

 " ventral arms, 

 " tentacular arms, 



club, .... 



is Pourtalesii. 



24 mm. 

 11 " 

 17 " 

 17 " 

 10 " 

 6 " 

 10 " 



6 " 



7 " 

 6 " 

 7.5 " 

 8.5" 



10 " 



30 " 



3 " 



Color of the dorsal and lateral surfaces of alcoholic specimen dark reddish 

 brown, due to a large number of chromatophores, which extend but a short 

 distance beyond the bases of the fins ; sides of the head, above the eyes, darker 

 brown ; ventral shield dark purplish brown, caused by great numbers of very 

 minute chromatophores ; its margin is surrounded by a pale band ; ai-ms and 



