I02 



MADOKA SASAKI. 



Also on the head, the luminous organs are irregularly distributed. Its 

 ventral surface exhibits about thirty-three large ones, of which eight are 

 arranged in a series just in front of the siphonal groove. Besides the 

 thirty-three, the margin of the right eye-opening shows a series of seventeen 

 large organs, and that of the left eye-opening a series composed of five 

 large ones in front and of four minute ones behind. The dorsal surface ot 

 head has five large and about eleven minute luminous organs. 



The luminous organs of ventral arms are arranged, in the proximal 

 half of their length, in three series ; more distally, they occur in two series, 

 and finally in the terminal parts they form a single series ; the series of 

 longest extent being the middle series made up of twenty-five organs. 

 The luminous organs of first, second and third arm pairs consist of a single 

 series of large organs on the ventral side, and of a single series of minute 

 ones on the dorsal. 



Buccal membrane broad, with seven ribs, projections and connective 

 ligaments. 



Radula with seven series of unicuspid teeth, which, as regards their 

 length, show the following relations : median = lateral == 1/2 inner 

 marginal = 1/3 outer marginal. 



Inner surface of mantle, siphon, buccal membrane, branchial vessels 

 and adductor muscles of siphon show a purplish brown hue, while the 

 anterior parts of neck as well as of siphonal groove are tinged with a 

 darkish brown color. 



Remarks. — Doflein's original specimen of this species was first taken 

 . by Chun to be identical with 6". ocellata (Owen 1906), but was later made 

 by Pfeffer into a new species under the name of S. doflcini. The specimens 

 now before me, as also the Doflein's specimen, do not quite agree with 

 ■ Owen's original description of S. ocellata. In his S. ocellata, the horny 

 ring of arm-suckers should have " a finely spinous border," which is not 

 the case in S. dofleini. Further, the former seems to have luminous organs 

 more numerously on head but less so on mantle than in the latter species, 

 while the arms are much shorter, being only a little longer than mantle. 



