•riKi KANSAS UNIVERSITY QUARTERLY. 



Muscina brunnea, nov. sp. 



One male ; Corumba ; May. Length, 7 mm. 



Ground color of bucca, ventral part of occiput, posterior orbit, 

 transverse impression of face, gena, vibrissal ridge, facial fossa, 

 epistoma and antennae pale brownish yellow ; all these parts 

 with more or less of a whitish or grayish pollinose coating, which 

 is thickest on the very narrow gena?. The bucca is beset ( not 

 verv densely) with black hairs, which, as usual, are longer 

 toward the occiput. The principal vibrissii? are a little dorsad 

 the free border of the clypeus. Ventrad the principal are sev- 

 eral secondary vibrissae. Dorsad the principal vibrissa^ the 

 vibrissal ridge is beset on its lateral surface with many exceed- 

 ingly small, bristly hairs. The transverse impression and the 

 gena are naked. The front is very narrow from a point just 

 ventrad the ocelli to about its ventral third and then widens 

 rapidly to the antennae, forming a frontal triangle whose cen- 

 ter, the vitta, is dark brown and whose sides, the geno-vertical 

 plates, are grayish pollinose. 



The geno-vertical plates are very narrow but bear an unin- 

 terrupted series of transfrontal bristles, which are, however, 

 very small, especially at the narrowest part of the front, where 

 they can only be seen with some difficulty. The black, vertical 

 triangle is only large enough for the ocelli. All the bristles of 

 the vertex are unusually small. The largest are the great ocel- 

 lars. There are about four pairs of tiny lesser ocellars. I 

 can make out, all about equal in size, the inner, outer and 

 postverticals. The occipito-central and occipito-lateral bristles 

 are absent. The cilia of the posterior orbit are short, but 

 form a complete row ; parallel to them, on the occiput, I can see 

 no rows of bristles. The dorsal part of the occiput is black 

 but white pollinose. The second anteunal joint measures 0.2 

 mm. ; the third joint, 0.7 mm. The arista is densely plumose, 

 its rachis yellow. The dorso-ventral diameter of the head is 

 2.7 mm. ; of the bucca, 0.3 mm. The palpi are pale brownish 

 yellow. 



The ground color of the thorax and scutellura is dark chestnut 

 brown, with pale brownish-yellow humeri and prostigma. This 

 ground color is obscured by a coating of grayish pollen, which, 

 however, leaves certain stripes and spots of the ground color 

 distinctly visible. These stripes and spots are best seen if one 



