348 Mr. R. M‘Lachlan on new Genera 
marginales posteriores quatuor: posticee parva. Pedes hir- 
sutiusculi; tibize cylindrice ; tarsi 2-articulati. 
In structure similar to the species of Psocus of the lineatus 
group, but remarkable for the different forms of the antennz in 
the sexes, those of the $ being strongly incrassate, whereas in the 
? they form a long jointed thread ; they are probably 10-jointed, 
but some of the apical joints are obscure. 
Eremopsocus infumatus, n. sp. 
$. E.nigro-fuscus, nitidus ; antennis pedibusque nigris ; capite 
oculisque nigro-fuscis; mesothorace lineis elevatis transversis 
literam % formantibus instructo; scutello lineis elevatis radiatis 
instructo ; alis anticis posticisque fuscis, nitidis, illis dimidio 
apicali pterostigmateque saturatioribus, venis nonnullis disci 
albido-hyalinis, pterostigmate magno, triangulari. 
@. Pallide brunneus; abdomine infuscato; alis haud_nitidis ; 
femoribus flavescentibus ; czeteris ut in é. 
Exp. alar..¢d 7 4 9 8s 
Habitat in Brasilia (Dom. Bates). 
In Muss. Oxon. et mihi. 
Psocus, Latreille. 
A. Tarsi 3-articulati.* 
a. Cellula discoidalis occlusa ; cellule marginales postertores 
quatuor. 
§ Plerostigma lberum. 
Psocus griseipennis, n. Sp. 
P. fuscus; antennis flavidis, fusco-terminatis; capite flavo- 
griseo, naso verticeque nigro-striatis ; scutello abdomineque 
flavido-variis ; alis anticis cinereis, fusco-griseo-marmoratis et 
reticulatis, venis longitudinalibus albido et nigro alterne punc- 
tatis, pterostigmate triangulari, antice elongato, griseo; alis 
posticis hyalinis, costa ad apicem albido nigroque punctata ; 
pedibus flavidis, tibiis hirsutiusculis, minute nigro-punctatis, 
femoribus maculis et tibiarum tarsorumque apicibus infuscatis. 
Exp. alar. 53—7”. 
Habitat in Australia. 
In Muss, Brit., Oxon., et mihi. 
This may possibly be the P. australis of Brauer (Verh. zool.- 
* In the species of Psocus with triarticulate tarsi, the second, or middle 
joint, is always small, and generally requires a careful examination under a 
high power, to define it with certainty. 
