58 ART. 4. 1. IKEDA : 



the Japan Sea) differ from those from other localities in having 

 fewer but larger hooks, 20-30 in number and about 0.06 mm. in 

 height. The tentacles are given oif from four stems : these latter 

 split each into two branches ; each branch again divides into 

 4-6 long tentacles which are of a violet color except at the 

 bright yellow tip. 



The longitudinal muscle is continuous. There exists only 

 one pair of retractor muscles (the ventral), originating in the 

 middle of the body proper or at a somewhat more posterior 

 point. The dorsal vessel, running along the dorsal side of the 

 œsophagus, bears numerous, tolerably long, contractile villi [cv, 

 Fig. 95). The intestinal convolution, consisting of 7-12 spirals, 

 is loose and irregular, especially in young specimens. The spindle 

 muscle is not attached to the body proper at the posterior end 

 of the body. The rectal portion of the intestine is tolerably long 

 and bears at its beginning a small blind diverticulum {rg). Of 

 fixing muscles there are present sometimes two, sometimes only 

 one and in still other specimens, none at all. When present in 

 a pair, both are attached to the first intestinal spiral and end 

 on both sides of the nerve-cord ; when present singly, the muscle 

 is on the left side. The segmental organs {so) are about one- 

 third as long as the body proper, and are entirely devoid of a 

 mesentery. Their external apertures lie at the same level as the 

 anus. Eye-spots are present on the ganglion. 



The present species in the manner of the branching of its 

 tentacles and in their color resembles Dendrosto7na alutaceum 

 Grube, but is quite different from that species in the form, size, 

 and structure of the papillœ, in the size of the hooks, in the 

 number of contractile villi and in the total size of the worm-body. 



Habitat : Specimens of the species have been collected at 



