PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 185 



usually with iiioiv or less distinct brownish mottlings along the sides, 

 due to internal organs. The two pairs of ocelli are rather distant, and 

 usually there is a dusky line extending between the two eyes of the 

 same side. On the head, in front of the eyes, there are often Hake- white 

 specks ; and frequently others occur along the middle of the back. ]Slot 

 before recorded from the American coast. 



Tetrastemma vittata Verrill. 



Amorican Joiimal of Science, vol. vii, p. 45, pi. 7, iigs. 3, a, h, 1874 ; Proc. Ainef. 



Assoc, for Adv. of Science for 1873, p. 389, pi. 2, tigs. 7, 8, 1874. 

 CosmocephaUi (f ) cordiceps (Sars, MSS. ), Jensen, Turbellariti ad Litora Norvegiie, 

 p. 8,>, lab. viii, tigs. 13-l(i, 1879. 



The species described by Jensen from the coast of Xorway agrees so 

 well, in form and color, with our T. vittata^ as to render its identity 

 highly probable. The eyes were not observed by Sars in the Norwegian 

 specimens, but they are often so obscured by the very dark color of the 

 head, in our darkest examples, as to be almost invisible. 



This species was dredged in considerable numbers this season in Cape 

 Cod Bay, 16 to 22 fathoms, mud, by the U. S. Fish Commission. Some 

 of the specimens were 3 inches long. 



Lineus viridis Yevrill {=^ Flanana rir\di» Fabr.). 



Linc'us Gesserensis M'Intosli. — Xemrrfes viridis Verrill, Report on Invert, of 

 Vineyard Sd., etc., p. 334 [(528]. 



This species is exceedingly abundant on our coast, from the Arctic 

 Ocean to Long Island Sound. It occurs gregariously under stones, be- 

 tween tides, and also at the depth of several fathoms. The most abund- 

 ant variety is gre6n, varying from dull olive-green to greenish black, 

 the anterior end usually darkest, and the ventral surface jjaler than the 

 back. The transverse light lines are usually indistinct. Length, often 

 150"™ or more. 



Xar. fasca (= PIfinario fnsca Fabr.). 



This variety occurs like the last, and is usually associated with it. The 

 color varies from pale reddish brown to dark brown and greenish brown. 



Lineus comtauuis Van Beneden. 



This species, accurately described and figured by Van Beneden, is very 

 common, often occurring in large groups under stones and among 

 nuiscles, on nuiddy shores, between tides (Eastport, Me., to Long Island 

 Sound). It imicli resejnbles tlie ])receding S])ecies in form and color, 

 but is n)(>rc slender, with a more elongated head, the mouth being 

 farther back. The color is usually dark olive-green to gieenish black, 

 but varies to brownish and dull reddish. Ocelli black, often rather in- 

 distinct in dark specimens, forming a single lateral row on each side of 

 the head. It is probable that L. socudis (Leidy sp.) is not distinct from 

 this. 



