306 THE ANNELIDA POLYCHAETA. 



Pakontjphis Ehlers. 



Mem. M. C. Z., 1887, 15, p. 67, 73, 78. 



Paronuphis solenotecton, sp. nov.^ 

 Plate 39, fig. 3-8; Plate 40, fig. 1, 2. 



This species, so far as indicated by the type-specimens, is decidedly smaller 

 than most species of Diopatra, the maximum length noted being only about 

 30 mm. The maximum width, exclusive of the parapodia, is 2 mm., and in- 

 clusive of the parapocUa, 2.25 mm. An incomplete specimen, the length of 

 which cannot be judged, has a maximum width, exclusive of parapodia, of 2.4 

 mm. No specimen removed from the tube was whoUy complete, the thinness 

 of the walls of the posterior somites resulting in easy breaking and disintegration. 

 The number of somites is hmited, as nearly as can be judged, being only about 

 forty. Body widest at from the twelfth to the sixteenth somite, from where 

 it narrows conspicuously cephalad and conspicuously, but more gradually, to the 

 caudal region, whence of uniform width to the pygidium, which narrows abruptly 

 to an acute point. 



The general color is brown. A pale ventral and dorsal median longitudinal 

 line, of which the dorsal is less distinct and over much of the length may be 

 scarcely or not at all evident ; both hues with a tendency to break into separated 

 dots. Parapodia also hghter colored, yellowish. Setae very pale. 



Prostomium as viewed from above broadly subtriangular, but with the sides 

 and the apex rounded, the whole sometimes appearing somewhat semicircular. 

 A transverse furrow or constriction, in line with the anterior edges of the anterior 

 lateral tentacles, separates off a subtriangular apical division. There is a trans- 

 verse furrow caudad of the unpaired tentacle, behind which the prostomium 

 is more elevated as a transverse ring, which is very short mesally. There is 

 also a semicircular furrow just in front of the median tentacle, with its convexity 

 forward. The frontal tentacles are attached on the front margin toward the 

 ventral side, extending cephaloventrad and at the same time diverging strongly 

 from each other. They are short and stout, being mostly only half, or less than 

 half, the length of the prostomium; in outhne, elliptic to broadly subconical, 

 with tip rounded. Either slightly removed from each other at base or in actual 

 contact. The anterior paired tentacles are attached a little caudad and ectad 



' au\(p, tube, and t(kto}p, artificer. 



