22 AßT. 4. J. IK EDA : 



papilke. The specimeus I collected on the shores of the Aomori 

 Bay, are enth*ely devoid of the characteristic markings on the 

 introvert, while the skin-papillse are in general unusually 

 tall. A form similar to the above is also frequently obtained 

 on the shores of Misaki. 



PHYMOSOMA JAPONICUM, Grube. 



Selenka, (28), 1883, p. 76. 



The main features of this species are embodied in the following 

 extract from Selenka 's description : 



Body proper of larger specimens, about 5 cm. in length ; 

 twice as long as introvert. Color, gray or grayish brown. Papilhe 

 visible as reddish brown specks ; they are formed of polygonal 

 plates arranged in concentric circles. About 25-30 hook-rows, 

 — in the younger individuals, sometimes even as many as 100, 

 — are present on the introvert. Hooks 0.07 mm. long, very flat 

 laterally, provided with two sharp teeth at apex, and with warts 

 (" Bunzeln ") at base. Tentacles, about 28 in number. Two brown 

 eye-spots present on the ganglion. 



Longitudinal muscles are divided into about 30, frequently 

 anastomosing bundles. Four retractor muscles arise from the 

 middle one-third of the body proper, the dorsal pair being rooted 

 in front of the ventral pair. Dorsal vessel tolerably long, without 

 contractile villi. Intestinal convolution consists of 10-12 double 

 spirals, traversed by a spindle muscle fixed at both ends to the 

 body-wall. A single fixing muscle is attached to the first intestinal 

 spiral. Two long and moderately large segmental organs extend 



