458 A. E. Yerrill — Dinophilidm of Neio England. 



base of the caudal segment, which is small, short-triangular, and 

 terminated by a tuft of large cilia. In the posterior part of the 

 body are two relatively large, ovate, opaque, reproductive bodies, 

 but whether they wei'e ovaries or spermaries I did not ascertain, so 

 that the sex of the specimen described and figured is uncertain, 

 but it is probably a female. Color whitish. Length -7""" ; breadth, 

 as compressed, 'IG'"™. 



Taken on the piles of a wharf at Wood's Holl, Mass., Aug. 1 0, 1 883. 



This species is closely allied to D. gyrociliatus of Europe. The 

 latter has, however, six post-oral segments, and differs also in the 

 form of the head, pharynx, and stomach. How much importance 

 should be attached to these differences is uncertain, for they may be 

 due largely to different conditions of the specimens examined. The 

 two may eventually prove to be identical. 



Dinophilus simplex, sp. nov. 



Plate xxxvi, figures 6. 6a. 



Body nearly smooth, distinctly segmented, in extension elongated 

 and more or less cylindrical, the anterior part usually broadest, com- 

 posed of four evident segments, exclusive of the large head and 

 abortive tail. Segments well defined, but without any conspicuous 

 bands of cilia. Head-segment large and long, subtriangular in front, 

 and often pointed, but sometimes rounded. Eyes nearly lateral, 

 small, but conspicuous. Mouth simple, elongated, situated between, 

 or a little in front of the eyes. Stomach long and not much en- 

 larged ; intestine nearly as wide as the stomach, terminating in a 

 nearly terminal anal pore. The tail segment appears to be rudi- 

 mentary or abortive. The sex was not ascertained. Color pale 

 yellow. Newport, R. I., Aug., 1880. 



The afiinities of this species are somewhat uncertain. The 

 pharynx and stomach differ considerably from a typical Dinophilus. 

 Reproductive organs were not observed. 



