Jan., 1922 synopsis of the genus stenocranus 81 



median carina extended all the way to apex of scutellum; elytra much 

 longer than abdomen, subhyaline, all veins and the interior margin 

 partly inf uscate ; wings hyaline ; dorsum and venter of abdomen fuscous ; 

 greater part of femora blackish-brown, tibiae with two blackish bands, 

 hind ones bispinose in front of the middle; tarsi light yellowish, partly 

 fuscous. Length of body, 4>^ mm. ; elytra, 4>^; width of meson, 1 mm. 

 "Country: Province of Buenos Ayres." 



Of this species I received from Sr. Ed. Lynch Arribalzaga, 

 one individual that was collected in Rio Lujan during the 

 month of February, 1879. 



A comparative study of the male genitalia of the members 

 of this genus show that dorsalis, vittatus, felti, angustus, similis, 

 and croceus are very closely related to each other. PalcBtus 

 and longicornis on the other hand form an entirely distinct type 

 of development with the py gofer more or less trilobate. Breviceps 

 shows a third type in which the ventral margin of the pygofer 

 is deeply and angularly emarginate. Hinei is the sole repre- 

 sentative of a fourth type having the pygofer formed of a 

 median and two lateral large teeth and with a single median 

 anal process. Rostrifrons is known from a single female and 

 therefore no comparison can be made of the male genitalia. 



The relation of these species to one another as shown in a 

 study of the genitalia is borne out by the external structure. 



The Genus Mysidia Westwood. 



Many of the members of this genus closely resemble certain 

 small whitish Geometrid moths. They run very swiftly on the 

 upper surface of leaves or when caught in a net, with their wings 

 partially raised. The genus is tropical, at least nine species 

 occurring in Central America and nothing is known of their 

 life-history. Heretofore no species has been known from North 

 America. 



For the most part members of this genus are of a white more 

 or less opaque color; the head is narrow and compressed; the 

 antennae have the first joint short, the second large and swollen, 

 more or less pointed or truncate, the third consisting of a fine 

 seta ; the tegmina are very long and rather narrow, much larger 

 than the wings, both vitreous, with the veins very light in color 

 with occasional more or less obscure markings. One of the 

 best characteristics of the genus is the large number of long, 

 narrow, and very regular apical areas. 



