362 



PSYCHE. 



[June 1S90. 



which are pale yellow ; the hind tarsi though 

 incrassated at the base taper evenly to the 

 last joint. Halteres honey yellow. Wings 

 somewhat lanceolate at their bases, gray, 

 with blackish veins; the third and fourth 

 longitudinal veins at first converge gently, 

 but on approaching the tip of the wing be- 

 come parallel, the fourth terminating a very 

 short distance in front of the tip. 



Habitat : jSIilwaukee Co., Wis. 



The three males in my collection 

 agree with the above description, which 

 will be found to differ somewhat from 

 Loew's account (Monograph, p. 340, 

 also Centuria 5. 92). The less pig- 

 mented hind legs in Loew^'s specimen, 

 taken in the White Mountains, may 

 have been due to immaturity. I believe 

 that my specimens represent the nor- 

 mal adult male, though it is, of course, 

 possible that they may belong to a west- 

 ern variety with highly pigmented hind 

 legs. Be this as it may, the differences 

 seem hardly of specific value. 



SyNARTHRUS CIXEREIVENTRIS, LOEW. $. 



To Loew the male of this species was un- 

 known. It differs from the female as de- 

 scribed by that dipterologist, only in the 

 structure of the antennae and the spinulation 

 of the legs, the coloring of my specimen 

 answering perfectly to the color-description 

 of the female. The first antennal joint is 

 rather slender, especially at its base, the sec- 

 ond overlaps the inner side of the third by a 

 large rounded flap as in the female; the third 

 ioint is long and tapers slowly to an acute 



point in such a manner as to have the con- 

 tour of its dorsal side remain straight or 

 slightly concave, while the contour of its 

 ventral edge is convex ; the pubescence cov- 

 ering the joint is shorter and less conspicu- 

 ous than in 5'. barbaiits, l^otw ■■, the arista 

 which is a little over half as long as the an- 

 tenna, is rather delicate and clothed with 

 scarcely perceptible pubescence. The spinu- 

 lation of the legs in the female is not de- 

 scribed by Loew, probably because it pre- 

 sented nothing worthy of remark. The male 

 has a delicate and rather long spine project- 

 ing from the upper surface of the tip of the 

 median femur, while there are six or seven 

 short, stift" and evenly graduated spines be- 

 fore the middle of its under surface; the in- 

 ner face of the median tibia has three widely 

 separated black spines; the posterior face of 

 each of the hind tibiae is armed with about 

 eight equidistant black spines, besides the 

 regular rows of shorter and smaller spines; 

 the two spurs at the apex are powerfully de- 

 veloped, of equal length, and, in my speci- 

 men, directed at right angles to the long axis 

 of the tibia; hind metatarsal joint with sev- 

 eral prominent spines on its under surface ; 

 on the inner face of its proximal end a pecu- 

 liar sickle-shaped spine, bent back in the 

 opposite direction to all the other spines, so 

 that its curved and pointed end comes to lie 

 near the tip of the tibia. This peculiar spine 

 is inserted near the middle of the metatarsal 

 joint, to the surface of which it is applied for 

 some little distance. The abdomen is small, 

 with small, black, and in my specimen, much 

 concealed hypopygium. Length 2.5 mm.; 

 length of wing 2.5 mm. 



Habitat: Milwaukee Co., Wis. 



(^To be concluded.^ 



