1903.] NATURAL SCIENCES OF PHILADELPHIA. 467 



curved, the exposed part lighter in color and spirally canaliculated 

 around a slender fibrous core which- usuall}' appears to be somewhat 

 eccentric. 



Notopodial seta? in a dense spreading tuft, longer than neuropodials 

 especially toward the dorsal margin of the Inuidles, but similar in form 

 to the second kind, the spiral canal of smaller calibre, and correspond- 

 ing to an external spiral raised line, \\hich latter alone persists toward 

 the end. 



SetSB of posterior region few in number (only about 6 or 8 in the 

 neuropodium), similar in both rami, very long, slender, straight and 

 stiff, longitudinally striated, the terminal half with a deUcate marginal 

 serrature which appears to be due to a series of about f collars sHghtly 

 overlapping, and on one side separated from the shaft by a distinct 

 space, thus foreshadowing the canaliculated form of seta. 



A few short delicate sette with bifid tips, the two divisions of which are 

 fringed on their opposed faces with fine hairs, also occur in the neuro- 

 podium. 



Anteriorly the neuropodial acicula are inconspicuous, but on the 

 13th to 16th parapodia inclusive they largely replace the ordinary setse 

 and become very much enlarged with subterminal thickenings, pointed 

 ends, and a deep brown color; they project as a row of 5-7 short spines, 

 except the dorsalmost one, which in most cases has its entire spindle- 

 shaped terminal half exposed. In the posterior region there are 3 

 neuropodial and one notopodial acicula, slender, acute, with the tip 

 sculptured for a short distance, exactly as in the setae. 



Suruga Bay, 3,709, 173-260 fms.; 3,724, 20 fms. ; North Japan, 

 3,768, 25 fms.; 3,771, 61 fms. 



CIRRATULIDJE. 



Cirratulus gibbosus sp. nov. (PL XXVI, fig. 72.1 



Form of preserved specimens stout anteriorly, flat below, strongly 

 arched above; slender, pointed, and much depressed posteriorly. The 

 type and largest specimen has 105 somites, is 32 mm. long, and 6.5 mm. 

 wide at XXX, the widest part. 



Prostomium a short and broad lip about 3 times as wide as long, 

 with a transverse row of 4 to 6 conspicuous, reddish-brown eyes on 

 each side of a median interval of about ^ the width of the prostomium. 

 Mouth small. Peristomium a prominent, swollen, gibbous ring, as 

 long as the prostomium and elevated above the level, both of this and 

 the succeeding somites. Next follows a neck-like region of 6 very 

 short somites without sette or branchiae. The succeeding few somites 



