MORGAN HEBARD 283 



as wide, instead of subqiiadrate, and even weaker blunt tuber- 

 culation of subgenital plate. Much the most important differ- 

 ences are found in the furcula and cerci. In size, form and 

 general appearance this species agrees fully with M. Ugneolus 

 Scudder, another very closely related species. The present insect 

 is particularly distinguished from all the forms closely related 

 to grocilipes by the much more elongate furcula. 



Females of these species are most difficult to separate. This 

 sex of hesperus is a little more slender and elongate than females 

 of graciUpes, in every way similar to females of Ugneolus except 

 in the very slightly more pronounced lateral carinae of the 

 pronotum."'^ 



Type. — (^ ; San Luis Obispo, San Luis Obispo County. Cali- 

 fornia. August 21, 1909. (M. Hebard.) [Hebard Collection, 

 Type no. 504.] 



Size small, but, with Ugneolus, largest of the species closely related to graci- 

 Upes. Form slender, much as in graciUpes and in M. huporeus here described. 

 Head much as in graciUpes, but wath area of fastigio-facial angle slightly more 

 produced, much as in huporeus, but with frontal costa appreciably wider, as in 

 graciUpes, showing only very slight concavity toward median ocellus. Eye 

 large, over two and one-half times as long as infra-ocular sulcus. Pronotum 

 elongate, disk of almost equal width throughout, median carina well defined 

 and percurrent, lateral carinae distinct though very weakly defined, not sub- 

 obsolete as in graciUpes or fully as weak as in Ugneolus, caudal margiii of disk 

 broadly obtuse-angulate produced, more produced than in graciUpes. Pro- 

 sternal spine as in graciUpes; elongate, bluntly subconical. Tegmina shorter 

 than pronotum, rather broadly oval, feebly overlajiping, with apex bluntly 

 rounded. Furcula represented by a pair of slender elongate processes, which 

 diverge at an angle of sixty (to ninety in series) degrees, three and one-half 

 times as long as greatest width, length contained in that of supra-anal plate 

 slightly less than two and one-half times, width about the same in pro.ximal 

 two-thirds and there separated by an interval of nearly equal width, thence 

 tapering to the acute apex. Supra-anal plate shield-shaped; surface with a 

 deep medio-longitudinal sulcus, running through i)roximal two-thirds, the 

 lateral carinae of this sulcus each with mere traces of a transverse carina 

 externally, mesad on the plate; surface with lateral portions rather strongly 

 concave in proximal two-thirds, beyond which two broad, longitudinal, parallel, 

 short ridges run to the free margin just before the apex. Between the supra- 

 anal plate and the cerci, a portion of a l)asal plate is extruded, this causing the 

 lateral margins of the plate to be somewhat elevated. Cerci moderateh- 

 elongate, weakly curving inward, about two and one-fourth times as long as 



■•^This feature is probably of little diagnostic value, as the degree of differ- 

 ence noted is easily within the limits of individual variation. 



TRANS. .\M. ENT. SOC, XLV. 



