396 bulletin: museum of comparative zoology. 



durch die ganze Ausdehnung des Thieres verlaufen." But the first 

 of these seem to be nothing but the rounded gelatinous prominences 

 which Chun has figured for veneris ('80, taf. 13, fig. 4). And as for 

 the latter, I can find nothing in Mertens's figure which I can thus 

 identify, and therefore am in some doubt as to just what was meant. 



The only structural feature which may separate amphitrites from 

 the Atlantic form is a slight apparent difference in the relations of 

 adradial to meridional canals. But Mertens's figure ('33, pi. 1, fig. 5) 

 is obviously somewhat diagrammatic, and not altogether clear. I 

 have considered amphitrites thus fully because a single Cestum was 

 taken which agrees with Mertens's figure in color, as well as in its 

 general form and structure, and which may therefore be identified 

 safely as amphitrites. Anatomically I was able to find nothing to 

 differentiate it from veneris : it agrees even in the proportions of the 

 various organs and canals; but unfortunately parts of the canals 

 were destroyed. 



Whether najadis can be referred to amphitrites, as its color suggests, 

 is doubtful, as pointed out above. There is one other Cestum the 

 color of which suggests that it probably does belong there, namely C. 

 pectenalh Bigelow from the Maldives. Moser (:08a) has pointed 

 out that my description of that species was unsatisfactory; and I can 

 go farther and say that the account, my first attempt at zoological 

 description, was founded on insufficient notes, and is therefore prac- 

 tically worthless. I have recently referred to my original drawings 

 (no specimens were preserved) and would state that the only details 

 which can be depended on are the general form and the yellow spots 

 at either extremity. 



Cestum amphitrites Mertens. 



Cestum amphitrites Mertens, '33, p. 492, taf. 0; L. Agassiz, '60, p. 

 291. 



Cestus veneris Chun, '80, p. 301 (partim). 



Cestus amphitrites Moser, : 08a, p. 14. 



^.Cestus pectenalis Bigelow, : 04, p. 267, pi. 8, fig. 30. 



Station 4546 Hyd. (14° 50' N. lat., 101° 31' W. long.). 

 One specimen, about 60 cm. long was taken, and several others 

 were floating on the surface. 



The specimen was in good condition, except for some damage 

 to the canals, and was kept under observation alive for some 



