378 PROCEEDINGS OF THE ACADEMY OF [1897. 



first fore tarsal joint with six to seven spines ; petiole black, shorter 

 than combined length of second and third hind tarsal joints; abdo- 

 men above and beneath with a distinct, sparse punctuation ; wings 

 subhyaline, not yellowish, apical margins broadly darker. Length 

 20-22 mm. 



$ . — Colored and clothed like the 9 , the fore margin of the cly- 

 peus in addition being sometimes reddish ; space between hind 

 ocelli a little greater than that between them and eyes; first joint 

 of flagellum shorter than the second and third united, the second a 

 little shorter than the third ; last ventral plate indistinctly carinated 

 down middle, its apex prolonged triangularly in the middle. Length 

 19-21 mm. 



Chapada (March, April, October) ; Corumba (April). Three 



9 , 10 <? specimens. Distinguished from ichneumoneus, dubitatus, 

 etc., by sparser pubescence, bright red of abdomen, strongly punc- 

 tured dorsulum (and clypeus in 9 ), shape of last ventral plate in 



$ , etc. 



Sphex {Priononyx) Thomae Fabr. 



Quite a large series of both sexes from various localities, collected 

 in the months of February, March, April, June, September. 



Sphex {Priononyx) bifoveolatus T;iscl>. 



Twenty-seven 9,13 $ specimens. Chapada (March, April, 

 November) ; Corumba (April). 



Psen aurifrons Tasch. 



Chapada (October, November). Two specimens. 

 Psen Smithii n. sp. 



$. — Black; antennae basally and beneath, mandibles medially, 

 tegula?, tubercles, fulvous ; tips of femora, four anterior tibia?, base 

 of hind pair, and tarsi, yellowish ; second abdominal segment at 

 base more or less reddish ; abdomen with a bluish metallic cast ; 

 head below antenna? with dense silvery or pale golden pubescence ; 

 vertex rather finely punctured ; ocelli in a triangle, the space be- 

 tween hind pair about equal to that between them and eyes, the lat- 

 ter converging beneath ; clypeus subtruncate or subemarginate 

 medially ; antenna? rather stout, perhaps a little shorter than head 

 and thorax ; dorsulum shining, sparsely punctured ; scutellum im- 

 pressed down middle ; mesopleura? punctured similarly to dorsulum ; 

 middle segment covered with coarse reticulations, the basal enclosure 

 small, with oblique ruga? on each side of a smooth, triangular, cen- 



