180 PROCEEDINGS OF THE ACADEMY OF [Vol. LXXV 



leaving the dorsal surface a little sunken. One specimen exhibits 

 a narrow brown line, probably a row of ocelli, near the anterior 

 border; this is absent or faded in the type. Arising from the trun- 

 cated apex is a slender, erect tentacle, about as long as the basal 

 width of the prostomium. On the ventral face of the prostomium, 

 is a small median tubercle which fits into a corresponding groove 

 in the peristomium. 



Peristomium a small, somewhat horseshoe-shaped ring beneath 

 the prostomium and surrounding the mouth ventrally and laterally. 

 Ventrally it is coalesced with II to form a slightly inflated lower 

 lip. Laterally it is free from II, and bears a pair of rounded bean- 

 shaped parapodial wings or lamellae, arising at the sides of the 

 prostomium, the two sides curving in front of these into the mouth 

 as a pair of conjoined hooks at the extreme end of each of which 

 is a minute globular appendage. Peristomial cirri (tentacles) are 

 lost. 



Anterior setigerous segments slightly depressed, generally about 

 two and one-half times as wide as long ventrally, but much narrower 

 dorsally. With the parapodia, the effect is of a marked ventral 

 convexity and dorsal concavity, though the segments themselves 

 are convex on both surfaces. Greatest width, both with and without 

 parapodia, at the fifth to seventh setigerous somites, behind which 

 the body tapers to about the fourteenth setigerous somite and 

 then remains approximately constant to the end of the piece. 

 Somite III bears on the ventral surface a pair of small approximated 

 papillae in contact with the caudal border of the lower lip. Succeed- 

 ing somites each bear a broad glandular ventral plate divided by 

 a transverse furrow into two nearly equal parts; beginning with 

 XVI these are gradually reduced and by XIX have disappeared, 

 after which the somites become smooth as on the dorsum. 



At from XVII to XIX the transverse dorsal membrane appears 

 as a low indistinct fold uniting the paired notopodia. This rapidly 

 becomes higher and involves the entire notopodium until by XXIV 

 it is three-fourths as high as the depth of the segment and forms a 

 prominent fold with a frilled, thickened, and apparently glandular 

 margin, and so remains to somite XL at least, the segments of 

 this region having the aspect of a lot of thin, ruffled disks, strung 

 together. 



Anterior parapodia are large, their length fully equaling the 

 width of their somites and, being turned dorsad, they impart to the 

 body the broad, depressed, concave aspect of this region All are 

 biramous and of the same type, but differ in relative proportions 

 of parts. The first four have the two rami separated, the noto- 

 podium well dorsad, with a rather prominent anteroposteriorly 

 flattened setigerous tubercle bearing a fan-shaped seta fascicle, and 

 a flattened, slender, lanceolate post-setal lamella. Neuropodia 

 generally similar, but the setigerous tubercle is larger and more 



