468 PROCEEDINGS OF THE ACADEMY OF [Juue, 



widen abruptly and these and all others are iiniannulate. Anus 

 minute, slightly dorsal. 



The branchise begin as a tuft of 3 or 4 small ones on each side of VIII 

 just above the parapodia; on IX a large tuft of upward of 15 arises 

 from a transverse area which extends from the parapodia nearly to the 

 middle line, while each of the succeeding somites back as far as the be- 

 ginning of the posterior i bears a single pair which arises close to the 

 posterior margin about midw^ay between the parapodia and the dorsal 

 mid-line, except anteriorly where the place of origin is lower and more 

 irregular. Posteriorly the size of the branchiae varies ; small and large 

 ones alternate in a very irregular way. 



The parapodia consist of small, well-separated neuropodial and 

 notopodial tubercles which begin with the setae on VIII. For about 

 the first 12 or 13 somites only capillary setae are present in the noto- 

 podial tubercles, beyond that they are mixed with blunt spines, while 

 all of the neuropodial tubercles contain both spines and capillary setae. 

 The number of both is always small, about 5 capillary in anterior 

 notopodia, usually 2 of each in anterior neuropodia, 1 of each in pos- 

 terior notopodia, and 1 capillary and 2 spines in posterior neuropodia. 

 Capillary setae little elongated, but few of them exceeding the distance 

 between the two setigerous tubercles, pale greenish, slightly obliquely 

 striated and fringed on one margin, slender, tapering. Spines simple, 

 slightly sigmoid, greenish yellow, translucent and unstriated ; one of the 

 notopodials usually somewhat enlarged. 



Sagami Bay, 3,703, 31 fms. 

 Chaetozone spinosa sp. nov. (PI. XXVI, figs. 73, 74.) 



The type, a complete specimen of 112 somites, is 65 mm. long and 

 5 mm. in breadth at the end of the anterior -J. The head is very dis- 

 tinctly separated from the body by a deep furrow behind the peristo- 

 mium, broadly top-shaped as seen from above, bluntly pointed and 

 about as broad as long. Prostomium nipple-shaped, separated from the 

 peristomium by a furrow dorsally and laterally, but on the ventral side 

 reaching back to mouth as a narrow pointed upper lip, behind which 

 is a pair of palp-Hke lobes bounding the mouth at the sides. Peristo- 

 mium much enlarged, considerably wider than the next somite and 

 fully twice as long above as below; smooth, regularly rounded, with 

 a faint transverse constriction above and laterally. No eyes and no 

 visible sensory pits. Mouth ventral, with an anchor-shaped anterior 

 extension between the palp-like lobes, bounded posteriorly by a smooth 

 under hp. 



Body somewhat depressed anteriorl}^, more or less quadrate posteri- 



