[17] ANNELIDS OF PROVINCETOWN, MASS. 715 



Other specimeus were larger and witli more segments ; in no case did 

 the length exceed l.S'"'". 



Low water 5 sand. 



A number of specimens, which we are quite unable to separate from 

 this species, were collected by Mr. Benedict at South l»[orwalk, Conn. 

 They differ only in the length of the buccal segment, which is hardly 

 visible dorsally. This is probably due to different states of contraction, 

 though it seems curious that all of the Provincetown specimens should 

 show the buccal segment plainly, and that none of the specimens from 

 South Norwalk should show it. 



Sph^eosyllis longicierata, n. sp. 



(PL. VIII, Figs. 95-100.) 



Head with the anterior and lateral margins (fig. 95) regularly rounded, 

 posterior margin very slightly convex, nearly straight. The posterior 

 part of the head, bounded in front by a curved line drawn through the 

 bases of the antennae, is elevated, convex, the part of the head in front 

 of this line being thin, depressed ; sometimes the depression is prolonged 

 backward between the eyes for a varying width, giving lateral ele%'^- 

 tions, on which the four posterior eyes are found. 



Eyes, six ; the two posterior pairs large, circular, nearly on the same 

 straight line j the anterior pair very small, just in front of the origin of 

 the lateral antennae. 



The antennae are somewhat fusiform, irregularly constricted, bluntly 

 rounded at apex ; median antenna one-third longer than the head and 

 palpi ; lateral a little shorter. 



The tentacular cijri, dorsal, and anal cirri have the same structure as 

 the antennae. The dorsal cirri originate some distance within the foot, 

 and are very long for the genus ; there is usually a deep constriction 

 at the outer third or fourth, setting off a fusiform api^endix. The anal 

 cirri may be double the length of the dorsal. 



The buccal segment, in extension, is as long as the second segment. 



The palpi are large, convex externally, concave internally, apex 

 bluntly rounded, anterior third free, connected by a thick membrane 

 along their posterior two- thirds; this membrane emarginate in front, 

 and divided into lateral halves by an impressed line, which runs back 

 to the head. 



The pharynx occupies four segments, the stomach two. 



The feet (fig. 97) are stout, nearly cylindrical, truncated externally. 

 The ventral cirri, bluntly conical, are about one-half the length of the 

 foot in front ; behind, as long as the foot. 



In each foot is a fan of compound setae and one simple seta (fig. 100). 

 The compound setae are very delicate, differing from each other only in 

 length (figs. 98, 99). 



Body, colorless ; stomach, white ; intestines, brown or yellow. 



