136 THOMAS SAY lOUNDATION 



Colorado, Xo. 1413 (Experiment Station) ; one Se- 

 attle, Wash. (Hough) ; one Erwin, S. Dak. 



Holotype.— Male, No. 20519 U. S. N. M., from 

 LaFayette, Ind. 



Several females collected at LaFayette, Ind., on 

 flowers of parsnijDS growing wild, along with males of 

 reversa and marginata, undoubtedly belong to one or 

 both of these species. They have much grayer color 

 than the males, which are comparatively dark; the 

 front in three specimens measured .300, .309, and 

 .325 of the head (average of .311) ; ocellars and or- 

 bitals as usual; bucca sloping upward anteriorly in 

 profile, and the stout vibrissfe slightly above edge of 

 mouth. Abdomen strongly tessellated, more than in 

 males; fifth and sixth sternites red or a little brown- 

 ish, the latter somewhat elongated and trough-shaped, 

 but straight. 



The characters given do not suffice to separate 

 these females from numerous specimens taken farther 

 west, which probably belongs to other species of the 

 closely allied group, in which even the males can 

 hardly be separated except by genitalic characters. 



No. 58. Sarcophaga marginata n. sp. 



Male. Characters like eiVcisa except as follows: 

 Front .148 of head. Antenna? reaching three-fourths 

 of the way to A^brissa?. Fourth abdominal segment 

 entirely black. Third costal segment as long as fifth 

 and sixth together. Forceps entirely yellow or only 

 the extreme apex a little darkened, with moderate 

 black hair at base ; beyond the middle of the free part 

 where they begin to bend forward there, is a thicken- 

 ing on the outer side surmounted by numerous rather 

 long slender little spines; apex with a minute hook 

 on front side ; viewed from behind the forceps diverge 

 from base and become suddenly wider on the outer 

 side a little past the middle. Accessory plate slender, 

 yellow. Posterior clasper very long, slender toward 

 the apex and strongly hooked. Anterior clasper 

 broad and stout. Penis with a very long basal joint, 



