AOCHLETUS. — EUPARHYPHUS. 39 



Thorax black, variegated with yellow ; a pair of longitudinal yellow stripes on the mesonotum, attenuated 

 at both ends, and reaching posteriorly the corners of the yellow scutellum ; a broad yellow stripe reaches 

 from the humerus to the hind coxae, encroaching in the shape of a triangle on the mesonotum, above the 

 dorso-pleural suture ; post-alar callosities yellow, with a small yellow triangle in front of them, on the 

 mesonotum ; on the black portions of the mesonotum an appressed golden pubescence. Abdomen black, 

 moderately shining, with a microscopic, black, erect pubescence ; lateral edges with a narrow, irregular, 

 jagged yellow margin, which, about the middle, expands into a semifascia rounded at the top, corre- 

 sponding to a similar semifascia on the other side and resembling a broadly interrupted yellow cross-band ; 

 venter yellow. Knobs of the balteres yellow. Front legs, including the coxae, yellow, the tarsi brown ; four 

 posterior legs, including the metatarsi, yellow, the last four joints of the tarsi brown ; hind tibiae with 

 interrupted brown lines ; hind metatarsus brownish at the tip. "Wings hyaline ; stigma more or less 

 infuscated ; the veins around it, the fifth vein, and the central cross-veins darker brown. 



Female. Like the male, but the silvery facial orbits are on yellow, and not black, ground ; front yellow, with 

 brownish shades ; a large black spot on each side, near the eye ; occiput black, the occipital orbits yellow, 

 silvery below, and with a narrow black edge, quite near the eye, on their upper half ; vertex brownish- 

 yellow ; ocellar spot black. The yellow stripes on the mesonotum are interrupted posteriorly some distance 

 before the scutellum ; in front they are slightly club-shaped, and not attenuate as in the male. Antennae 

 dark brown, slightly reddish at the base of the flagellum only. 



Length : c? , 4 millim. ; $ , 4-5 millim. 



Hab. Mexico, Northern Sonora (Morrison). Two males, one female. 



EUPARHYPHUS. 



Euparhyphus, Gerstaecker, Linnaea Entomol. xi. p. 314 (1857) . 



To the characters of this genus given by Gerstaecker I would add that, in the male, 

 the eyes are subcontiguous, the front, below the vertical triangle, being linear ; the upper, 

 larger, facets are separated by a well-marked horizontal line from the lower ones ; both 

 portions of the eye also differ in colour. The E. decem-maculatus, which I describe 

 below, has pubescent eyes. Two of the species described by Loew have no branch to 

 the third vein, that is, they have only a single submarginal cell. 



Only American species are known ; the one from Africa, described by Bigot, does 

 not belong to the genus. 



The North-American and Mexican species hitherto described may be grouped as 

 follows : — 



Scutellum black, sometimes yellowish at the tip ; spines yellow. 

 Femora black, except the tip. 



A single submarginal cell tetraspilus, Loew. 



Two submarginal cells bellus, Loew. 



Femora yellow (except posterior pair at the tip) stigmaticalis, Loew. 



ornatus, Willist. 

 Scutellum yellow or red. 



Abdomen with lateral yellow spots. 



Two lateral spots on each side brevicornis, Loew. 



Three oblique yellow spots on each side ; a row of spots in the 



middle decem-maculatus, sp. n. 



