JAPANESE PALOLO, CERATOCEPHALE OSAWAT, N. SP. / 



segments may be said to present a light pinkish eolor. For the 

 rest the ventral surface is of a pale flesh color. 



In the specimens preserved in alcohol, the coloring matter 

 has dissolved away, leaving only a light bluish hue on the anterior 

 dorsal surface of the body. 



Prœslomium (PL II., fig. 9). — This is small and flat, but well 

 developed. The shape may be said to be subhexagonal, consisting 

 of a transversely elongate, eye-bearing section attached by a broad 

 base to the peristomium, and of an anterior section which somewhat 

 narrows towards the bases of the tentacula at the front edge. The 

 sides of the head at the junction of the two sections are concave. 

 The anterior section is divided into two halves by a median groove. 



The tentacula, present in a pair and situated close together 

 on the anterior edge of the head, are small, being of a length 

 less than half that of the entire head. Their base is slightly 

 pigmented, the remaining part being colorless. 



The subten taenia, likewise in a pair, are attached to the 

 sides of the head at their anterior concave part as well as to the 

 peristomium. They are thick and fleshy, with a small, round, 

 somewhat retractile boss at the tip. Except at this end, which 

 is colorless, they are of a brownish color. 



The eyes, of which there are two pairs, are situated close to 

 the lateral borders of the hind section of the head. In the 

 anterior pair they are more widely separated from each other 

 than in the posterior. Moreover, in the former they are directed 

 forwards and outwards, while in the latter their direction is 

 upwards and outwards. In alcoholic specimens the eyes are 

 scarcely visible, so that with only such specimens one might be 

 misled into assuming their absence. 



