240 PROCEEDINGS OF THE ACADEMY OF [April, 



incisions, behind which it is more erect and diminishes in height to a 

 minute median posterior notch. Anterior to the lateral incisions the 

 rather abruptly widened and flaring margins continue undiminished 

 almost to the palpode which they join on each side. The cephalic 

 margin is everywhere smooth and its margin entire. A pair of con- 

 spicuous sensory slits divide the central disk of the head for about 

 the anterior five-sixths of its length into three narrow longitudinal 

 areas of equal width which are united behind. The central one is 

 somewhat ridged and widens almost imperceptibly as it passes into 

 the palpode anteriorly. The palpode consists of a short rounded base 

 bearing a slender, elongated finger-like process on its median anterior 

 margin. 



The cephalic plate forms a dorsal angle of about 120° or less with the 

 peristomium, which is indistinguishably coalesced with the prostomium. 

 It is little more than one-half as long as the cephalic plate and its sur- 

 face is slightly granulated but unwrinkled. Owing to the protrusion 

 of the proboscis, which has a depressed acorn-shape, with the basal 

 division thickly papillated, the mouth is invisible. 



Somite II (the first setigerous) has a length about equalling the 

 width at the anterior end, from which it gradually diminishes in dia- 

 meter caudad. The next two segments are narrowerer, after which 

 the diameter increases gradually to VIII, though the length remains 

 nearly constant ; IX has the same diameter, but if complete is scarcely 

 half as long as VIII, All of these segments are transversely wrinkled 

 superficially and are provided with a distinct, raised neural line. No 

 prominent collars but merely a low free rim, most distinct on V, are 

 developed on their anterior ends. 



Owing to the much coiled and twisted condition the real proportions 

 of the distorted posterior segments cannot be easily ascertained. They 

 are evidently three or four times as long as wide, slender and thin- 

 skinned, except posteriorly where the prominent, swollen and glandu- 

 lar parapodia are developed. There are no especially developed 

 glandular zones or muscular ridges and the neural line is elevated 

 throughout. The last six or seven segments decrease in length and the 

 entire region tapers to the pygidium. The first of the posterior achae- 

 tous segments is about one and one-half times as long as wide and of a 

 shape similar to those preceding it, having fully developed but naked 

 tori on the posterior end. The next three are simple rings without 

 tori and of rapidly decreasing length. Terminating the body is a 

 remarkably small, top-shaped pygidium lacking any limbate margin. 

 Instead there arises around the base of the anal papilla, which con- 



