106 BULLETIN OF THE 



Arms considerably longer than the head and body, not very stout, com- 

 pressed, bearing a single crowded row of large whitish suckers, which are 

 mostly separated by spaces less than half their diameter, margins of suckers 

 soft and much thickened. The three lower pairs of arms are very nearly equal 

 in length and size; the dorsal ones are a little shorter and smaller. A thin 

 web unites all the arms for about one fourth of their length, and runs up along 

 their sides for about half their length. The male has the third right arm 

 (Plate V. fig. 1) hectocotylixed at the tip ; the modified tip is preceded by 45 

 suckers, and is bordered ventrally by a broad membrane, having a white groove 

 along its inner surface ; the terminal organ (Fig. 1») consists of a small, ovate- 

 triangular, fleshy disk, with its inner surlace slightly concave and finely wrin- 

 kled transversely, and terminating proximally in a small point. 



Color dark purplish brown, darker purple beneath. Chromatophores small 

 and densely crowded. 



The female is considerably larger than the male, and has the warts over the 

 back and around the eyes relatively smaller, but of the same character. The 

 arms appear to be larger than those of the male, but this is probably due to 

 the fact that the male has become more contracted by the stronger alcohol in 

 which it was placed. 



This female specimen illustrates well the uselessness of the attempts to 

 divide the species of Octopus and allied genera into groups or sections according 

 to the relative lengths of the arms, as J. E. Gray and others have done, for in 

 this and many other cases the proportions of the arms of the right side would 

 throw it into one section ; those of the left side into another. The male would 

 have to be put into a third section. 



MEASUREMENTS IN MILLIMETERS. 



No. 12. No. 13. 



Male. Female. 



Righ t side. Left side. 



Total length 202. 360. 



End of body to centre of eye 58. 100. 



Breadth of body 55. 65. 



Breadth across eyes 49. 



Length of dorsal arms, from mouth ... 135. 255. 260. 



Length of 2d pair of arms 155. 260. 235. 



Length of 3d pair of arms 225. 240. 



Length of hectocotylized ami 130. 



Length of modified tip 4.5 



Length of ventral ai-ms 145. 210. 225. 



Greate.st breadth of lateral arms .... 12. 18. 18. 



Diameter of largest suckers 3. 5. 5. 



SPECIMENS EXAMINED. 



Specimen* 

 No. Stat. Locality. Fath. When rec'd. No. Sex. 



12 305, N.Lat. 4103.3' 15", W. Long. 6.'}° 51' 25' 810 1880 1 d 



13 312, N. Lat. 30° 50' 45", W. Long. 70° 11' 466 1880 1 9 



