CEPHALOPODA. — BERRY. 243 



25) show 13 to 16 acute teeth alternating with an equal 

 number of thin, arcuate plates, here again the upper median 

 tooth being conspicuously the largest. To better bring out 

 these small differences I here append figures of homy rings 

 from both a sessile arm and tentacle club of the type speci- 

 men (dorsal mantle length 138 mm.) of 0. hawaiiensis. Figs. 

 17 and 19 show similar structures from a female specimen of 

 N. gouldi of only slightly larger size (dorsal mantle length 

 180 mm.). Other differences in the two species worth noting 

 are the relatively larger head of hawaiiensis, the apparently 

 fewer and larger arm suckers, and the much shorter fins. 



The radula of iV. gouldi reminds one very much of that of 

 O. sloanii as figured by Hutton (1882, pi. vi., fig. B). It is 

 also surprisingly similar to that of Ommastrephes sagittatus 

 as figured by Girard (1890, pi. — , fig. 3e), though not at all 

 like those of the other genera of the family as he illustrates 

 them. This bears out the evidence of other structural 

 features that Nototodarus is exceedingly nearly allied to 

 Ommastrephes s.s. and quite possibly to be regarded as a 

 comparatively recently more highly specialised offshoot from 

 the latter. 



The small, round, thin transparent " window " in the 

 integument of the ventral surface of the head covering the 

 eye, so well shown in Pfeffer's figures of New Zealand Otnma- 

 strephes sloanii and other Ommastrephids, can be made out 

 in the " Endeavour " specimens. Its probable function is 

 a puzzle, but it puts one strongly in mind of the similarly 

 situated transparent membrane which overlies the subocular 

 photophores of Watasenia, Enoploteiithis, and allied genera, 

 and permits the better escape of the light rays. On this slim 

 ground I have made a careful search for subocular photogenic 

 organs in Nototodarus, but have been unable to demonstrate 

 their presence. On a more favourable occasion I hope by 

 recourse to sectioning to settle the matter conclusively. 



Division MYOPSIDA. 



Family LOLIGINID^. 



Genus Loligo, Schneider, 1784. 



LOLIGO ETHERIDGEI, Sp. nOV. 



(Plates Ixvii.-lxviii. ; Plate Ixix., figs. 1-2.) 



Animal of moderate size, of the characteristic Loligo 

 outline. Mantle cylindrical in front, slightly swollen near 

 the middle, thence tapering between the fins to a moderately 

 acute point behind. Fins large, about three-fifths as long 



