1908.1 NATURAL SCIENCES OF PHILADELPHIA. 



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about 5 times the length of the head and the ventral only about twice 

 that length. Remaining somites are very short anteriorly, but from 

 the twentieth onward are only 6 or 7 times as wide as long. Dorsally 

 they are strongly arched, ventrally flattened. The intersegmental 

 furrows are well marked, perhaps exaggerated by contraction of the 

 longitudinal muscles. 



All of the parapodia (a and h) are prominent and spring from the 

 lowest level of the sides of the body. Notopodia are entirely wanting, 

 even the acicula appearing to be absent. The neuropodia, on the other 

 hand, are stout, those at the anterior end being nearly truncated, 

 while the more posterior ones are bevelled from the dorsal or acicular 

 angle. All, however, possess slender and prominent presetal papillse 

 at this angle. Ventral cirri are remarkably large and swollen on the 

 anterior parapodia and end bluntly, but farther back they become 

 reduced in size and more slender and an annular constriction may 

 separate the pointed end as a separate piece. 



The most striking characteristic of the species is the great length 

 of the anterior dorsal cirri which form a tangled mass at the sides of 

 the body; they are so easily detached that few of them remain. 

 They arise from rather stout but short cirrophores (a) which are not 

 sharply distinguished from the sides of the somites. The styles are 

 smooth, tapering and very slender toward the end, like whiplashes. 

 On one of the smaller specimens, which has 29 segments measuring 8 

 mm. long, and a maximum body width of 3 mm., the dorsal cirrus of 

 somite IV measures no less than 14 mm. long. The cirri are alternately 

 longer and shorter, and after about the first ten those borne on the 

 even numbered somites are regularly 2 to 2^ times the body width, 

 while those on the odd numbered somites little exceed the body width. 

 Neuropodia are supported by 5 or 6 acicula which taper gradually 

 almost to the end, where they are slightly curved and end abruptly in 

 short conical points. The setae (c) project rather prominently in usu- 

 ally 5 subacicular ranks of 3 or 4 each. In any one parapodium they 

 are remarkably uniform in length of blade, etc., but the blades become 

 gradually shorter and wider and the shafts stouter from before back- 

 wards. The shaft (c) exhibits but a slight distal enlargement, but is 

 conspicuously and very unequally bifid, the larger and longer process 

 ending quite acutely and being provided along the front with 4 or 5 

 obscure teeth. The blades or appendages are rather long, strongly 

 hooked and bifid at the end, and especially noteworthy for the coarse- 

 ness of their marginal serrations. 



With the exception of the prostomium and the dorsal cirri these 



