A. E. Verrill — Marine Nemerteans of New England, etc. 405 



Tetrastem7na grcenlandicum Diesiug-, op. cit., p. 259. 



Tetraslemma Candida Mcintosh, British Annelids, Part I, Nemerteans, p. 167, pi. ii, 

 figs. 2, 3, 1873 (non Diesingr, Syst.); Levinsen, Groenlands Turbell, p. 39 [200], 

 1879; Verrill, Amer. Jour. Sci , vol x, p. 40, 1875; Check List, 1879. 



PL.4.TE XX.XIII, FIGURES 9, 10, lOft; PL.\TE XXXV, FIGURES 9, 10. 



Body very contractile, in extension slender, elongated, somewhat 

 depi-essed, tapering backward and often attenuated toward the 

 posterior end. Head in usual extension rather wider than the body. 

 Ocelli rather large, conspicuous, reddish brown, nearly in a square, 

 but when the head is fully extended, the two pairs are farther apart 

 than the distance between those of a pair. 



Color variable, usually pale green, greenish white, or yellowish 

 white, translucent, and generally with indistinct lateral grayish 

 mottling, due to the internal organs; sometimes the intestinal area 

 is decidedly greenish, while the sides are pale yellow ; at other 

 times the median region is whitish and the sides pale green. 

 Several specimens, taken at Eastport, Me., in South Bay, 8 to 10 

 fathoms, mud, 1868, were clear cream color above, whitish below. 



Length in extension 25 to 32™"^; diameter 1 to 2'""". 



Common at many localities between tides, among alg?e, hydroids, 

 and bryozoa from New Haven, Conn., to the Bay of Fundy. Also 

 dredged at moderate depths, 1 to 14 fathoms, in many localities. 



This species is very active ; it creeps rapidly with a gliding 

 motion. The relatively larger size of the head, more conspicuous 

 eyes, and lighter colors, as contrasted with the following species, are 

 its most distinctive characters. 



It seems to me very doubtful whether the Planarki Candida of 

 Fabricius was this species. The large size and the habits given by 

 him, and lack of mention of the eyes are against that view. His 

 species may have been Amphi-iw^-us lactifloreus, a Greenland species. 



Tetrastemma Candida. Variations. 



Several specimens of the variety figured on |)late xxxtii, figs. 10, 

 10a, were taken on the piles of the wharves at Gloucester, Mass., 

 July 24, 1878. These were probably not full grown. The body 

 was 8 to 12"'"" long, in extension, slender, very changeable, usually 

 of nearly uniform breadth to near the ends. Head obtuse and 

 usually a little wider than the body, but very changeable in shape; 

 when extended the ocelli were farther apart longitudinally than 

 transversely, but when the head contracted, as in progression, the 

 two paii's of ocelli were broiight near together', as' shown in the 



