44 KANSAS UNIVERSITY QUARTERLY. 



2. Oonops grandis, n. sp. 



Female. Front black, the lower margin of the vertical callosity 

 reddish; just below the callosity opaque, elsewhere shining. Anten- 

 nae black; the second and third joints of nearly equal length; the 

 first joint about two-thirds the length of the second joint; style with a 

 long bristly extremity. Face and cheeks light yellow, the orbital 

 margins of the former silvery or light golden pollinose. Thorax 

 black, the mesonotum shining, the pleurae lightly whitish pollinose. 

 Abdomen deep black ; posteriorly lightly pollinose. Wings brown in 

 front; first posterior cell and the space behind the streak correspond- 

 ing to the spurious vein of the Syrphidae in the first posterior cell, 

 pure hyaline ; outer part of the first posterior cell subhyaline ; a brown 

 streak in front of the fifth vein. Legs black ; the tibiae and basal 

 joints of the tarsi in large part reddish or yellowish; pulvilli light 

 yellow; ventral process of the fifth segment extraordinarily large; 

 seventh segment as long as the three preceding together. 



Male. Abdomen in ground-color black, either wholly so, or more 

 or less, or rarely entirely, red ; the ground color, save at the base, 

 however, is almost wholly obscured by reddish brown pollen. 



Length 19-23 millimeters. Six specimens, Chapada, H. H. Smith. 



3. Oonops rufus, n. sp. 



Male, female. Head red ; face in the depression yellow, on the 

 sides with a silvery sheen. Antennae black ; first joint red, more than 

 half of the length of the second joint; second joint sometimes reddish 

 at the base; third joint about as long as the second joint, stout; third 

 joint of the style suddenly attenuated into a moderately long bristly 

 extremity. Thorax red ; mesonotum with a median black stripe, and 

 an oval, more or less distinct spot on either side; a golden pollinose 

 spot on the inner side of each humerus. Abdomen red, lightly pollin- 

 ose, the median segments more or less black ; ventral process in the 

 female large ; the sixth segment in the same sex about as long as the 

 two preceding together. Legs red. the tarsi a little darker, the pulvilli 

 and the ungues, save their black tip, yellow. Wings brown in front, 

 the brown extending to the fifth vein in the basal part of the discal 

 cell ; the space behind the spurious vein in the first posterior cell 

 hyaline; the outer part of the same cell subhyaline. 



Length 16-17 millimeters. Two specimens, Chapada, H. H. Smith. 



4. Oonops angustifrons, n. sp. 



Male. Front much longer than wide ; black, shining at the vertex 

 and below; an opaque band below the vertical callosity. Antennae 

 black, the third joint somewhat reddish below towards the base; the 

 first joint about half of the length of the third joint; third joint dis- 



