ISOPOD8 OF NORTH AMERICA. 21 



other two. Chelipeds in female rather strong, with the hand consid- 

 erably dilated, oval triangular in form, and scarcely smaller than the 

 carpus, with a slight dentated crest in front at the insertion of the 

 dactylus, the latter crested along the middle, thumb distinctly serrated 

 at the end inside; those in male with the hand much narrower than in 

 female, and furnished inside with a transverse row of about ten flat- 

 tened spines increasing in length behind, fingers quite simple, pointed, 

 the immovable one quite short. Uropoda in female attaining half the 

 length of the metasome, both rami biarticulate, the inner one more 

 than three times as long as the outer, and tipped by rather long setae; 

 inner ramus in male distinctly triarticulate. Length of female 3.75 

 mm., of male 2.55 mm." G. O. SARS. a 



3. Genus HETEROTANAIS Sars.& 



Eyes distinct. Abdomen with all six segments well defined. Pleo- 

 poda normal, all five pairs present. Uropoda biramous, outer branch 

 small, inner elongate and composed of four to five articles. Incu- 

 batory pouch normal. First gnathopods in female normal, in male 

 very different, being imperfectly chelate, thumb very short, or trans- 

 formed to a posteriorly-pointing lappet. 



HETEROTANAIS LIMICOLA (Harger).c 



Paratanais limicola HARGER, Am. Jour. Sci., (3) XV, 1878, p. 378. 



Leptochelia limicola HARGER, Proc. U. S. Nat. Mus., II, 1879, p. 163; Report 

 U. S. Commissioner of Fish and Fisheries, 1880, Pt. 6, p. 424, pi. xin, 

 figs. 87-88. 



Heterotanais limicola SARS, Archiv for Math, og Naturvid., 1882, p. 31. NORMAN 

 and STEBBING, Trans. Linn. Soc. London, XII, 1886, Pt. 4, p. 109. HANSEN, 

 Videnskabelige Meddelelser fra den naturhistorisk Forening in Kj0ben- 

 havn, 1887-1888, pp. 178-179. RICHARDSON, American Naturalist, XXXIV, 

 1900, p. 2.12; Proc. U. S. Nat. Mus., XXIII, 1901, p. 503. 



Localities. Massachusetts Bay, off Salem; Godthaab, Greenland 

 (Hansen). 



Depth. Forty-eight fathoms in soft mud; 40-60 fathoms. 



Body narrow, elongate, 2 mm. long and less than mm. wide. 



Head a little longer than wide, gradually becoming narrower from 

 the base to the anterior end. Eyes "small and inconspicuous." The 

 first pair of antennas have the first article very long; the second article 

 is only one-fourth as long as the first; the third is almost twice as 

 long as the second. The second pair of antennas have the first two 

 articles short and subequal; the third article is as long as the first two 

 taken together; the fourth is about half as long as the third. The 



Crust, of Norway, II, 1899, p. 27. 



6 See Sars for characters of genus, Crust, of Norway, II, 1899. 



c See Harger for description of this form. 



