270 THE ANNELIDA POLYCHAETA. 



Onuphis nannognathus, sp. nov.^ 

 Plate 43, fig. 8-11; Plate 44, fig. 1-5. 



This species is represented in the collection only by the anterior region of 

 a single specimen. This fragment is composed of one hundred and nineteen 

 somites, so that the number in the complete animal must be very large. The 

 fragment is 64 mm. long, with a maximum width, exclusive of parapodia, of 

 4 mm., the species being robust. 



The body is dark brown. On each side just above the parapodia a longi- 

 tudinal band of whitish yellow, which may extend mesad a variable distance in 

 a line along the edge of each somite, and anteriorly on a limited number of 

 somites a median longitudinal white line. Ventrally on each side there is a 

 broad yellowish band running from the fifth somite caudad over the glandular 

 areas at bases of parapodia. The tentacles are dark like the body, but the 

 branchiae and cirri are much paler, being light yellow. 



The prostomium is very short; subcylindrical, but flattened on the ventral 

 side. Dorsally the usual median longitudinal sulcus is only vaguely indicated. 

 The tentacles are arranged at the circumference of a transverse subelliptic area. 

 Ventrally a median longitudinal sulcus running caudad. The frontal tentacles 

 are prominent, subconical, distally rounded processes which at present are 

 contiguous at base, though, as the specimen seems considerably shrunken, 

 this may not be the condition in fresh specimens. The palps are large bodies 

 contiguous at the middle and elongate transversely. The dorsal tentacles 

 consist, as usual, each of a conspicuous, strongly annulated ceratophore and a 

 long smooth style. The inferior paired tentacles, if stretched back against the 

 body, reach somite IV. The ceratophore of each inferior paired tentacle 

 consists of six or seven very short but strongly marked annuU and a long smooth 

 distal division about one third the total length; it is cylindrical throughout. 

 The style is stout, and is pointed at the tip. The upper paired tentacles reach 

 to or near somite XVII. The ceratophore of each has nearly the same diameter 

 as that of the lower paired tentacles, but it is considerably shorter; it consists 

 of five or six very short, distinct articles, of which the most proximal is largest, 

 and a long, smooth, or but vaguely wrinkled distal division. The style, stout 

 at base, is strongly attenuated distad, the distal portion fine. The median 

 tentacle is equal in length to, or slightly longer than, the upper paired ones. Its 



' ub.vvo%, dwarf find 71'aflos, jaw. 



