ISOPODS OF NORTH AMERICA. 31 



and near the distal end with a hirger process; the dactylus is more 

 than half the length of the propodus and is strongly curv^ed. The six 

 following pairs of legs are small and similar in shape, the dactylus in 

 the second pair being only about twice as long as in any of the other 

 five pairs. The dactylus in the last three pairs is more curved than in 

 the three preceding pairs. 



In the female the first pair of antennjie are not elongated; the second 

 and third articles are subequal and each is about half as long as the 

 first. There is no fiagellum. The first pair of legs is not elongated; 

 the second pair have the dact3dus elongated as in the male. 



FiG.31.— Leptochelia rapax. o, First leg of male, x 27j. b, First lki; of female, x 27^. 



LEPTOCHELIA? FILUM (Stimpson). 



Tannis filum Stimpson, Siiiithf^oniaii CoutributioiiK to Knowledge, VI, 1858, 

 p. 43.— Harger, Am. Jour. Sd., (3) XV, 1878, p. 378. 



Leptochelia Jilurii Harger, Proc. U. S. Nat. Mus., II, 1879, ]>. 164; Report U. S. 

 Comm. of Fish and Fisheries, 1880, Pt. 6, p. 427.— Sars, Archiv for Matli, 

 eg Naturvid., 1882, p. 28. — Richardson, American Naturalist, XXXIV, 

 1900, p. 212; Proe. U. S. Nat. Mus., XXIII, 1901, p. 504. 



ZocaUties. — The Hake Bay, Grand Menan; Gulf of St. Lawrence. 



Depth. — Eight fathoms, on a sandy bottom; 20 fathoms among 

 Ascidise callosse. v-j 



" Very minute, slender, rounded on the back, white, looking very 

 much like a short piece of thread. Head small, and rather nar- 

 rowed in front; first thoracic segment of great length; the second 

 half as long as the third, which is about equal in length with the 

 fourth, fifth, and sixth; the seventh being a little shorter than the 

 sixth. The segments of the abdomen are well defined, the first five 

 equaling each other in length, and the terminal one longer than the 

 fifth, but narrower, and rounded behind. Antenna^ short and thick, 

 without tiagella, with blunt tips crowned with few hairs, as are also 

 their articulations. The inner ones are directed forward, and much 

 the stoutest, especially toward their bases; while the outer ones are 

 more slender and curve outward and backward. First pair of legs 

 exceedingly thickened, with very large ovate hands and strong curved 

 fingers. They are generally closely applied against the breast. The 

 remaining thoracic feet are very slender, terminating in sharp, slender 

 fingers, which in the second pair are very long and nearly straight, 



