AKT. 26 WASPS OF SUBFAMILY PSENINAE MALLOCH 51 



Type.—U.S.l^M. No. 44221, from Arizona (no. 2546, Baker col- 

 lection). 



The antennae are typical in general shape to those of normal 

 females of the genus, but the number of segments is that usually 

 found in males, so that the possibility of the type being a 

 hermaphrodite is extremely remote. 



PSENIA SUFFUSA (Fox) 



Plate 2, B^igukes 23, 29, 3(), 37 



Pseti suffusus Fox, Trans. Amer. Ent. Soc, vol. 25, p. 18, 1898. (Female.) 



This species was originally described from females only, and it is 

 surprising to discover, if my determination is correct, that there is a 

 striking sexual dimorphism in the species, the male being slenderer 

 and having the mesopleura very much more deeply and more closely 

 punctured than the female. The abdomen in the male has merely 

 the apices of the tergites on basal half red with a greater extension 

 of that color on the venter, while the female has the apex of second 

 and usually the basal half or more of the third segment red. 



Structurally the male is very similar to that of the next species, 

 but the characters listed in the key readily separate them. In 

 clavicornis the form of the abdomen is similar to that of this and 

 the next species, but in neither of the latter is the antennal fiagellum 

 at all clavate or lacking sensory areas. I believe the structure of 

 the sensory areas is sufficent to distinguish suffusa and longiventris 

 from their allies, and an important additional character, present to 

 the same degree in both sexes, is the exceptional central width be- 

 tween the carinae on the center line of the ventral surface of the 

 head. I figure the male hypopygium of su^usa to show the relative 

 positions of the various segments comprising it (pi. 2, fig. 36). The 

 female has the pygidial area fully twice as long as its width at 

 center, the mesopleura sparsely supplied with rather large punctures, 

 smaller and more closely placed on eps 2, the enclosure of the propo- 

 deum more closely reticulated than in longiventris^ and the areas 

 laterad of it very finely striate up to the curve where they become 

 reticulate. The abdomen of the female is stouter than in the male, 

 with shorter petiole and wider bases to the sternites. 



Length, 6.5-8 mm. 



Originally described from Las Cruces and Kincon, N.Mex. I have 

 a large series of both sexes before me, two being from Las Cruces. 

 The others are from the following localities : Mesilla, 2 miles north of 

 Vado, and La Luz, N.Mex. ; Phoenix, Higley, Tucson, and Sacaton, 

 Ariz. ; and Lindsay and Kedlands, Calif. 



I am quite confident that Fox had more than one species in his 

 type series as he states that the abdomen may be more preponder- 



