REVISION OF STREPSIPTERA PIERCE. 129 



Mesothorax: Length = 10; least breadth = 25; greatest breadth = 

 38(?). 



Balancer, or elytron: Length = 39. 



Metatho rax: Length = 122; prsescutum plus scutellum = 56 ; post- 

 lumbium = S ; postscutellum = 56; greatest breadth =53. 



Abdomen: Length tenth segment = 15; length cedeagus = IS. 



Anterior leg : Trochanter = 30 ; femur =30 (?) ; tibia = 45 ; tarsus = 35. 



Median leg: Trochanter = 32; femur = 33; tibia = 36; tarsus =31. 



Posterior leg : Trochanter = 15; femur = 39 ; tibia = 29 ; t arsus =31. 



In addition the following measurements were taken by cruder 

 methods : 



Length of body = 3.8 mm. 



Length of head and thorax = 2.4 mm. 



Breadth of head = 1 mm. 



Length of wing on costal margin = 2.6 mm; on anal margin =2.8 

 mm. 



Female. — Length of cephalothorax 1.57-1.77 mm., breadth at 

 spiracles 1.67-1.71 mm., breadth at base of head 1.35-1.36 mm., 

 distance between mandibles at base 0.28-0.35 mm. Cephalothorax 

 light brown with a broad dark-brown band at base; broader than 

 long; margin convex from base to apex, slightly depressed or concave 

 in front of mandibles; spiracles not laterally prominent; mandibles 

 distant from lateral margins of head, deeply bilobed at apex, the 

 inner lobe acute, the outer obtuse. 



The larger measurements are from a specimen from Polistes rubigi- 

 nosus taken at Waco, Texas, and which may belong to a distinct 

 species. The species is variable, as shown by specimens in the same 

 lot, and may even include A. maximus, since the ratios for this 

 species are included in each case within the range of A. pecosensis. 



Cotypes.— Cat. No. 10120, U.S.N.M.; and in Academy of Natural 

 Sciences, Philadelphia. 



6. ACROSCHISMUS WHEELERI Pierce (1908). 



Xenos jpechil Brues, 1903. 



Host. — Polistes metricus Say, Colebrook, Connecticut, August; 

 Washington, D. C, September 6, 7 (U. S. D. A. 3513°) (pi. 5, 

 figs. 8, 9, 12, 13; pi. 9, fig. 10). 



The following description is from Brues - 



Male. — Length, 3^4.5 mm. Dark fuscous, abdomen usually lighter and pale at 

 apex. Mandibles black at base, pale at tips, antennse yellowish gray, the rami of 

 third joint about one and one-third as long as the width of the head. Head fuscous. 

 Palpi indistinctly two-jointed, the second joint only one-half as long as the first and 

 not separated from it ventrally, so that the palpus appears to be obliquely cleft, the 

 first joint being obliquely truncate at apex. Dorsum of thorax varying from fuscous 

 to piceous, darkest medially, elytra gray. Abdomen usually yellowish gray above, 



