LUMBRINERELS HIFILARIS. 327 



LuMBRiNEREis Blainville. 



Diet. sci. nat., 1828, 57, p. 486. 



Scoleloma Blainville, ibid., p. 492. 



Lumbriconereis Grube, Archiv. naturges., 1851, 17, p. 45. 



Eranno Kinberg, Ofvers. K. vet. akad. Forh., 1865, no. 4, p. 567. 



LUMBRINEREIS BIFILARIS Ehlers. 



Plate 60, fig. 6-9; Plate 61, fig. 1. 



Lumbriconereis bifilaris Ehlers, Abhandl. K. gesellsch. wiss. Gottingen. Math. phy.s. klasse, 1901, 

 p. 139, pi. 18, fig. 1-10; Moore, Proc. Acad. nat. .sci. Philad., 1911, p. 291. 



In a specimen from Sta. 3418 there are 135 segments exclusive of the head. 

 The length is about 107 mm., with the maximum width, exclusive of parapodia, 

 6 mm., this being attained near the twelfth somite. But this width changes 

 but little and only very gradually caudad, the body appearing almost uniform 

 in width; a little in front of the caudal end the width is 5 mm. This is an ex- 

 ceptionally robust specimen, but others form a complete transition to the more 

 slender and usual form. 



Prostomium acuminate from the base as usual, sides a little convex, and 

 anterior end acutely rounded; depressed, the ventral surface fiat, with a median 

 longitudinal furrow, and the dorsal surface moderately convex, with a slight 

 crescentic elevation at base; thick at base, decreasing in thickness distad; 

 wider across base than long. 



Peristomium crossed on lower part of sides and ventrally by a series of 

 fine sulci which laterally are faint but ventrally become distinct and end in 

 an emargination in the anterior border. Palpal cushions well marked, simple, 

 rounded tubercles, or pads, which are wider than long. 



The parapodia of the specimens here listed have the usual character. In 

 the anterior parapodia there is a distinct, postsetal, foliaceous lip which is at first 

 low and extends proximad along the ventral surface, and a smaller, presetal, less 

 foliaceous lip as well. In proceeding caudad the postsetal lip becomes more 

 and more elongate and finger-like, extending in a caudal direction; the presetal 

 lip more slowly elongates, but in the posterior region is as long as the postsetal 

 process and extends more or less dorsad ; the processes are slender and mobile 

 and commonly much exceed in length the parapodia proper, this showing con- 

 siderable variation in the preserved specimens. 



Both the hooked and the capillary setae are long. The limbate capillary 

 setae are distally of the form shown in Plate 60, fig. 8, 9. A typical hooked seta 



