ISOPODS OF NORTH AMERICA. 



411 



(•/ . Propodns of first pair of legs armed with two processes, one triangular and the 

 other truncate. Second pair of antenn;e shorter than the body. Inner 

 l)rancli of uropoda twice as long as outer branch. 



yinncaseUu^ danielsi Richardson 



MANCASELLUS BRACHYURUS Harger. 



Manntacllus hmchi/iirHn Hargeu, Am. Jour. Sci. and Arts, (3), XI, 1876, pp. 304- 

 305.— Underwood, Bull. 111. State Lab. Nat. Hist, II, 1886, p. 359.— Boval- 

 Lius, Bihang till K. svenska V^et.-Akad. Ilandl., XI, No. 15, 1886, p. 39.— 

 Rkhakdson, American Naturalist, XXXIV, 1900, p. 296; Pro*;. U. S. Nat. 

 MuH., XXIII, 1901, p. 551. 



Localities. — McKee's spring, Lexington, Virginia; Gaylord, 

 Virginia. 

 Keported injurious to water cress. 



I 



Fig. 460.— Mancasellcs brachyurus. a, Abdomen with vropoda. x 9}. 6, Second pleopod of 

 MALE. x2~l. c, First pleopod OF FEMALE. X 27i. d, Third pleopod OF male, x ISJ. e, Uropod. 

 X 27i. /, First lec x 271. 0, Third pleopod of female, x loi. h, First pleopod of male. 

 X 27i. 



Body about two and a third times longer than wide, H nun. : 1-1 mm. 



Head a little more than twice as wide as long, 1^ mm.: 3^ mm., with 

 the anterior margin slightly excavate between the antero-lateral angles. 

 The sides of the head are entire. The e3^es are small, round, com- 



