122 



BULLETIN 66, UNITED STATES NATIONAL MUSEUM. 



between the spiracles to the distance from spiracles to apex, 

 third and fourth are of greatest importance. 



The 



Species. 



maximus. 

 pecosensis 

 rubiginosi 

 hubbardi. . 



texani 



pallidas. . 



bruesi 



hunteri.. . 

 wheeleri.. 

 nigrescens 

 bowditchi. 



Cephalothorax 

 to mandibles. 



(5) : (3) : :-: 1. 



5.58 

 4. 78-5. 78 

 5.25 

 5.90 

 5.09 

 5.54 

 4.95-5.00 

 5. 52 

 4.80 

 4.42 

 4.87 



Head Cephalothorax 



to mandibles. to head. 



(4): (3) ::-:!. (5) : (4) : :-: 1. 



4.53 

 3. 83-4. 08 

 3.87 

 4.67 

 3.88 

 4.00 

 3. 95-4. 00 

 4.37 

 4.00 

 3.36 

 3.84 



1.23 

 1.23-1.25 

 1.35 

 1.26 

 1.46 

 1.38 

 1.25 

 1.25 

 1.22 

 1.31 

 1.25 



Breadth 

 to length. 



(5) : (2) : :-: 1. 



1.05 

 1.52-1.77 

 1.31 

 1.32 

 1.32 

 1.38 

 1.00-1.80 

 1.45 

 1.52 

 1.08 

 2.43 



I. ACROSCHISMUS HUBBARDI Pierce (1908). 



Xenos, species Hubbard, 1892. 



Xenos hubbardi Pierce, in determinations. 



Host. — Polistes (americanus Fabricius) crinitus Felt; Crescent 

 City, Florida, April 6. Described from fourteen males in the collec- 

 tion of the U. S. National Museum, collected by H. G. Hubbard 

 (Hubbard, 21). It is upon these specimens that Hubbard based his 

 valuable observations on the life history of Xenos (pi. G, figs. 1-12; 

 pi. 9, fig. 3). 



Male. — Wing expanse 5.5 mm., length 2-3 mm. The specimens 

 measured, respectively, 2, 2, 2, 2.25, 2.5, 2.5, 2.5, 2.5, 2.75, 3, 3, 3, 3 mm. 



The following description was published by the present author in 

 1908: 



Color, brown. Antennae apparently brown, but on closer inspection transparent 

 yellow with blackish brown pubescence; first joint yellow. Face fulvous, pubescent; 

 mandibles transparent yellowish, glabrous. Vertex dark, head brown, eyes black. 

 Prothorax and mesothorax dark with elytra yellowish, pubescent, darker at club. 

 Metathorax lighter, brownish, with exception of postscutellum, which is dark brown. 

 Wings milky white, hyaline, irridescent, with dark brown costal margin; veining 

 delicate yellowish brown, pubescent gray; last three veins very light. Legs yellowish. 

 Abdomen yellow with black borders (Pierce, 1908). 



Antennae a little shorter than width of head, very sensitive pubes- 

 cent; the first with a veil-like curtain extending beyond and envelop- 

 ing the entire second joint, but so transparent that the second joint 

 is easily made out when viewed with a microscope. Maxilla? yellow, 

 two-jointed, with the first joint longest and somewhat obliquely 

 truncate (the second joint is the palpus). Mandibles acute, some- 

 what curved, ensiform, about twice as long as maxillae. Eyes 

 stalked. Prothorax and mesothorax about equal in length, each 



