178 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 56. 



Sculpture of the head finely punctulate, very minutely and aluta- 

 ceously so in iceryae and axillaris, but more distinctly so in other 

 species, especiaUy in niger, the postorbital region and occiput smooth 

 or with indistinct sculpture except in niger, which has a reticulate 

 sculpture on the postorbital region, and a fingerprint-like sculpture 

 on the occiput; fronto vertex with small, shallow pin-punctures more 

 or less regularly arranged in several rows but sometimes absent as 

 in iceryae; pronotum and mesoscutum finely scaly-reticulate as in 

 Homalotylus, the axillae and scutellum with a similar, but generally 

 coarser and more deeply impressed sculpture than the scutum, and 

 not opaquely punctulate as in Homalotylus; pleura and dorsiun of 

 abdomen sculptured as in Homalotylus, but the reticulation on the 

 abdomen generally much more uniform in size and regular in shape- 



Pubescence throughout as in Homalotylus, the mesepimera being 

 silvery pubescent like the metapleura. Coloration black, or black 

 variegated with yellow, brown or orange ferruginous, often shiny, 

 but never distinctly metallic. 



Male. — Hardly differing from the female except in the primary 

 sexual characters. 



Type of genus. — Isodromus iceryae Howard. 



The species so far as known all parasitize Chrysopid larvae and 

 Issue from the cocoons of their hosts. At least two species, iceryae 

 and niger, are also kno^^^l to attack Hemerobiids. 



Of the species belonging to Isodromus, intermedius (Boheman) 

 was synonymized by Thomson with vinulus (Dalman), chrysopae 

 (Ashmead) is here synonymized with puncticeps (Howard), and two 

 recent species of Girault, pulcJier and nigriaxillae appear to be nothing 

 but color variations of iceryae Howard, differing only in the exten- 

 sion of the yellow marldngs. For the latter species Girault need- 

 lessly erected the genus Parataneostigma and incomprehensibly 

 placed it among the Tanaostigmatini. The species belonging here 

 were included by Mayr in Homalotylus, and by Thomson in Nohrimus. 



Isodromus abnormicornis Girault * does not conform with Iso- 

 dromus in several particulars, and should be placed in the new genus, 

 BretJiesia, described below. 



KEY TO THE SPEaES OF ISODROMUS. 



1. Wings with a large brown spot beneath the stigmal vein 4 



Wings without a large brown spot on the disk. 



General color black or blackish brown varigated with yellow or mostly j'ellow. . . 2 



Head and body entirely black, except that the face and frons in the male are 



yellow; antennae dark brown, front and middle legs brownish yellow, the hind 



legs brown, the middle and hind tarsi and middle tibial spur yellowish white. 



1. niger Ashmead. 



1 Insec. Insc. Menst., vol. 4, Jan., 1917, p. 118. 



