296 



BULLETIN OF THE BUREAU OF FISHERIES. 



Type locality. — Oahu (first locality mentioned), Hawaiian Islands (Wilkes expedition). 

 Distribution. — Hawaiian Islands: Oahu (Gould); Honolulu Reef, Oahu (Albatross); Maui (Gould). 

 Material examined. — Three specimens, all males, are in the Albatross collection. All are in an 

 excellent state of preservation. 



Remarks. — The above description is drawn throughout from the specimens taken by the A Ibatross, 

 special reference being had to the larger of the two individuals collected on the reef, as the large market 

 specimen did not come into my hands until afterward and has been chiefly utilized in preparing the 

 description of the hectocotylized arm. It will at once be noted that there are several rather astonish- 

 ing discrepancies between these specimens and Dr. Gould's description. Perhaps the most important 

 of these is the relative length of the arms, which Gould states to be 2. 4, 3, 1, an utterly different formula 

 from that shown by the present material. As the quantitative differences between the arms of the 

 respective pairs seem altogether too great for such variations to be due to inequalities in the methods 

 of preservation, I am at a loss to account for the discrepancy. It is of course possible that an error has 

 crept in somewhere, for the Albatross specimens show not the slightest evidence of any abnormality, 

 while Gould's account of the consecutive diminution in bulk of the arms is entirely in accord with 

 the condition I have described, though not at all what would be expected were his statement of their 

 relative order of length correct. It may be that the type specimen was possessed of some unobserved 

 defect, for where the arms are so slender as in the present species a mutilated and regenerating extremity 

 might be readily overlooked were not special care taken to the contrary. The peculiarly definite 

 color pattern is in all the specimens as striking as Gould's careful description would imply and is so 

 utterly unlike that of any other Polypus known to me that I think there can be no doubt as to the cor- 

 rectness of the identification. 



Granting this correction in the arm formula, it is interesting to note that the resemblance of this 

 species to the Polypus macroptis (Risso) becomes even more close than Gould supposed and extends 

 even to such structures as the hectocotylus and funnel organ. (Cf. Jatta, 1896, pi. 23, fig. 8.) A com- 

 parison with the figures cited shows that the two species are throughout essentially similar in structure 

 and indicates a very close degree of relationship. The geographical distribution of both forms yields 

 additional strong evidence toward the same conclusion and further supports the idea that P. macropu! 

 is in fact the parent form. Although ornatus is thus far known only from the Hawaiian Islands, macro- 

 pus has a remarkably wide and continuous range, extending from the Mediterranean, on the one hand, 

 through the Red Sea and Indian Ocean to the Malay Peninsula and even to Japan, where it is still a 

 hardy and abundant species Small differences between the two are numerous and constant, but 

 perhaps are in no way different from the inevitable changes which should be expected to take place 

 in the island species during the long sojourn which it must have had in so isolated an environment. 

 It is curious that the color pattern and surface ornamentation are the features which have undergone 

 the most extensive modification. 



Polypus hoylei Berry 1909 (PI. xlvij, fig. 1; PI. xlviii, fig. 2-4; PI. lv, fig. 1.) 



Polypus hoylei Berry 1909, p. 407, 418, text fly. 1. 



Body pouch shaped, rounded, more or less depressed above and below, about as long as broad, 

 widening posteriorly and with an obscure longitudinal groove forming an incipient superficial division 

 of the ventral region into halves. Mantle loose and semigelatinous, very soft to the touch ; at 



