442 PROCEEDINGS OF THE ACADEMY OF [June, 



larger, having a length of 28 mm. for 54 anterior somites, and a maxi- 

 mum breadth of 2 mm. The posterior parapodia contain spermatozoa. 



Prostomimn of form usual in the genus, shghtly longer than peri- 

 stomimn; ventral furrow not especially deep and lobe not widely 

 divergent ; frontal tentacles occupying entire ventral end of lobes and 

 bounded by completely encircling furrows. E3'es 1 pair, brown, near 

 posterior margin of head, directly below and in contact with base of 

 inner lateral tentacles, not at all concealed by cephalic fold of peri- 

 stomium. Tentacles relatively short, only very faintly articulated, 

 the median lost in both specimens; inner lateral of seven joints and 

 reaching to posterior end of somite VI; outer lateral of 4 or 5 joints 

 and reaching to III. Peristomimn distinct, of equal length all 

 around and shghtly less than prostomium, with which it is not fused 

 laterally. 



Second somite about ^ length of peristomium, distinct, nuchal 

 (tentacular) cirri slender, very faintly articulated and reaching ante- 

 riorly to base of inner lateral tentacle, or posteriorly to the middle of 

 IV. As usual the somites in the region of greatest branchial develop- 

 ment are shorter and more crowded than either anterior or posterior 

 to this region. The last 8 or 9 somites taper rapidly to the anal ring, 

 which is slightly enlarged. Caudal cirri 2 pairs, the hinder very 

 slender and dehcate, equalling 11 last somites, the short one scarcely 

 equal to the width of the anal ring. 



Except for their somewhat greater prominence and the peculiarities 

 of the neuropodial cirri, the parapodia have the characters usual in 

 the genus. The tenth parapodium has the 2ieuropodium roughly 

 square in form, with the suprasetal portion more vescicular, tvmiid and 

 enlarged than usual in small species, the acicular lobe between the dor- 

 sal end of the series of compound setae, and the fascicle of capillary setae 

 prominent. The very characteristic neuropodial cirrus has an en- 

 larged basin-shaped swollen base, the hollow of which looks ventro- 

 laterad, while the terminal process is a thick, short, rounded process 

 of its dorso-lateral margin, the whole, in certain views, having a striking 

 resemblance to a mortar and pestle, Notopodial cirrus separated by 

 an interval from the neuropodium, double its length, the basal half 

 slightly swollen and receiving into its root the ends of 2 slender curved 

 acicula, the terminal half slender and obscurely articulated. 



Toward the anterior end the neuropodium is reduced in size, the 

 depression in the base of the neuropodial cirrus is lost, and the base 

 becomes first spherical and finally cylindrical, the notopodial cirrus 

 approaches the neuropodium, becomes relatively longer, with a more 



