1909.] NATURAL SCIENCES OF PHILADELPHIA. 285 



and surrounded by prominent papillae, often arranged in groups, 

 and encrusted with fine sand grains, a particularly prominent group 

 of about four forming a small tuft supported on a narrow pedicle in 

 the mid-dorsal line between the first pair of notopodial setae fascicles. 



Anterior end broadly rounded, the first few segments decidedly 

 depressed but increasing in depth rapidly until by about VI they 

 have become terete. These segments are short, crowded and some- 

 what telescoped, so that each one somewhat overlaps the next anterior, 

 especially dorsaUy where this feature is emphasized by the greater 

 prominence of the cutaneous papilla?. Remaining segments very 

 regular, simple and smooth, with clean-cut though shallow furrows 

 and from one-sixth to one-third as long as wide, becoming propor- 

 tionately longer as the diameter decreases posteriorly. Pygidium 

 a simple ring entirely lacking cirri. 



Integument thick and tough and more or less coated with a hard, 

 adhesive layer of fine sand, beyond which the tips of only the larger 

 papilla? project. On the venter and posteriorly the surface is nearly 

 smooth and the incrustation thin, but on the anterior dorsal region it 

 becomes rough and much thicker, forming, with the papillae, projecting 

 anterior margins to the segments and ensheathing even the larger 

 papillae nearly to their ends. The larger cutaneous papilla? are arranged 

 as follows: On the dorsal field is a transverse row of six or eight 

 projecting forward from the cephalic margin of each anterior segment. 

 In the ventral field on each side of the neural line and generally near 

 the middle of the segment is a single clavate papilla, replaced on more 

 anterior segments by a group of two or three; from one to three more 

 occur ventrad of the neuropodium. Surrounding the latter is an 

 irregular ring of papillae composed usually of one or two dorsal and 

 ventral, two to four anterior and usually three posterior, the middle 

 one of the last group being much larger than the others and elevated 

 prominently on a conical base. A similar ring surrounds the noto- 

 podium, the postsetal group here also consisting of one or two of 

 moderate size, and one very large one, often equaling the segment in 

 length anteriorly and elevated on a base which may bear the smaller 

 papillae as well. Passing from before caudad all of these papillae 

 gradually diminish in length, but their arrangement is constant. 



Except on the first two or three segments, on which they are more 

 crowded, the parapodia consist of widely separated notopodial and 

 neuropodial nearly or quite sessile tufts of setae. The former are 

 fan-shaped fascicles of five to eight (the larger numbers on middle 

 segments) flexible capillary setae. Those of the first four (II to V) 



