412 PROCEEDINGS OF THE ACADEMY OF [1899. 



side near base; remaining dorsals more strongly punctured, the 

 second ventral Avitli coarse irregular punctures; wings dark viola- 

 ceous; second submarginal triangular, with a ver}' small radial side, 

 the first and second transverso-cubital veins nearly uniting above; 

 third submarginal broadest above, the outer nervure gently bowed. 

 Length 13-14 mm. 



Chapada, January and March. Z. rufy^es is very similar to Z. 

 fraternns in general apj)earance, but is quite distinct. 



Zethus cristatus n. sp. 



Black; thorax and abdomen Avith thin silky pile; a dot behind 

 the base of each antenna, a linear spot on each side of pronotum 

 anteriorly, dot on tegulse anteriorly, line on postscutellum inter- 

 rupted medially, spot at tip of fore femora, one at base of four 

 anterior fibise, and a fascia at apex of abdominal segments 1-5 

 (that on segment 1 extending a short distance along sides), yel- 

 low ; Avings subhyaline, fuscous along costa, nervures black. 



?. — Head with strong deep punctures, running into striae on 

 front and becoming sparse on cheeks which are shining; clypeus 

 fully twice as broad as long, coarsely striato -punctate, angulate at 

 sides, the fore margin slightly incurv^ed, with two strong widely 

 separated teeth; antennae with flagellum short, clavate, its first 

 joint much shorter than the following two united, the scape fully 

 as long as the combined length of pedicel and following four 

 joints; space between hind ocelli equal to a little more than half of 

 that between them and eyes; pronotum strongly cristate, slightly 

 dentate laterally, deeply punctured ; dorsulum coarsely punctured, 

 confluently so anteriorly, more sparsely posteriorly, strongly impressed 

 anteriorly in the middle, and with two impressions, nearly parallel, 

 posteriorly ; scutellum impressed ; middle segment impressed, con- 

 cave, the convex portions rugoso-striate, the rugse extending a 

 little on the sides, which are nearly smooth and are separated from 

 the upper surface by a carina; basal stem of petiole about as 

 long as hind coxae and trochanters, the swollen portion elongate- 

 ovate, but not much narrowed posteriorly, with scattered shallow 

 punctures ; second segment Avith pedicel short and thick, shorter 

 than the Avidth of apex of petiole, finely and A^ery closely punc- 

 tured, except a few shalloAV punctures along the apical margin, the 

 ventral surface Avith the punctures larger and less close, but not 



