428 PROCEEDINGS OF THE ACADEMY OF [1899. 



cristate, not dentate ; dorsukim with strong, separated punctures 

 throughout, with a raised line anteriorly in middle, the posterior 

 impressions indistinct; scutellum rather flat, impressed, punctured 

 about like dorsulura ; postscutellum entire ; middle segment, con- 

 cave or depressed medially, finely striated except in depressed 

 middle, the lateral carina very short only present at base ; stem of 

 petiole short and stout, the enlarged portion fusiform, strongly 

 punctured except toward apex where the punctures are finer and 

 quite dense; second segment finely and closely punctured above, 

 the ventral surface smooth at base, and with large sparse punc- 

 tures apically, stem long and slender, about as long as first hind 

 tarsal joint, Avith distinct separated punctures ; second submarginal 

 cell with a radial side which is fully equal to the distance between 

 the fii'st transverso-cubital and first recurrent nervures on the cubi- 

 tal nervure; third submai'ginal rhomboidal, higher than long, 

 scarcely broadened above, the outer nervure gently sinuous. 

 Length 19-21 mm. 



d^. — Colored like ?, but Avith a yellow stripe on anterior margin 

 of clypeus and on mandibles ; sculptured more coarsely than in 9 ; 

 antennae hooked at tip, the ultimate joint obtusely pointed, much 

 longer than the penultimate, the two together not much longer than 

 the eleventh joint. Length 18 mm. 



Chapada, January, March, November, December ; Corumba, 

 April. Thirteen 9 and two c? examples. In this species, which may 

 be the same as Z. Smithii Sauss., the male has the fourth joint of 

 labial palpi distinct, Avhereas in the ? it is rudimentary. This 

 peculiarity seems to exist in several species of the section Didy- 

 mof/adra. 



Zethus simillimus n- sp. 



Very close to pundatus in coloration; but having all the femora 

 more or less reddish, and there is no yellow on hind tibiae, while 

 abdominal segments 3-6 are broadly margined with, or entirely, 

 yellow; otherwise colored as in pundatus 



9. — Front rather closely striato-punctate, the vertex finely and 

 closely punctured; clypeus twice as broad as long, with strong 

 shallow punctures becoming deeper anteriorly, the fore margin 

 dentate, or subdentate at each side, and very indistinctly so medi- 

 ally; dorsulum with strong punctures becoming sparse and weaker 



