REVISION OF STREPSIPTERA— PIERCE. 



153 



23. Genus CRAWFORDIA Pierce (1908). 



Type of genus. — Crawfordia pulvinipes Pierce, 1904. 



Dedicated to the honor of J. C. Crawford, who captured the type 

 species and thus first interested the writer in this group of insects. 



This genus is confined to North America. The hosts belong to the 

 genus Panurginus in the Panurgida?. 



It is characterized by the peculiar shaped oedeagus which, arising 

 at the apex of the abdomen, quickly dilates from a slender tube into 

 a bent inflated vesicle, which again suddenly narrows into a very 

 acute curved process. 



The genus has the xenid characters of four-jointed antennae, and 

 four-jointed tarsi, but has apparently three-jointed maxillae. 



Key to females. 



In the genus Crawfordia the female cephalothorax is very different 

 from that of Stylojjs, so that the comparative ratios will be consid- 

 erably different. The measurements are with 160 tube, 2-inch eye- 

 piece, A objective, Zeiss stand, 1 space = 0.0076 mm. 





1. 



Length. 



2. 



3. 



4. 



5. 



6. 



Species. 



Spiracle 

 to apex. 



Breadth 

 between 

 mandi- 

 bles. 



Breadth 

 head. 



Breadth 



at spira- 

 cles. 



Greatest 

 breadth. 





92 

 81 



60 

 50 



27 

 19 



SO 

 85 



85 



88 



87 



•pulvinipes 



88 







From these figures the following ratios, which are derived as in the 

 discussion of Stylops, are obtained : 



S] ii rii'S. 



Cephalothorax 

 to mandibles. 



(5):(3)::-:l. 



Head to 

 mandibles. 



(4):(3):-:l. 



Cephalothorax 



to head. 



(5):(4):-:l. 



Breadth to 

 length. 



(5):(2):-:l. 



eockerelli. . 

 pulvinipes. 



3.14 

 4.63 



2.96 

 4.47 



1.06 

 1.03 



1.41 

 1.76 



i. CRAWFORDIA PULVINIPES Pierce (1904). 



Xenos pulvinipes Pierce, 1904. 



Xenoides pulvinipes Pierce, 1905, in correspondence. 



Crawfordia pulvinipes Pierce, 1908. 



Host. — Panurginus, new species; West Point, Nebraska, August 

 10; collected by J. C. Crawford, in whose honor the genus is named. 

 Types in writer's collection (pi. 12, fig. 7; pi. 13, figs. 4, 5a, 5b, 6, 7). 



Male. — Antenna? four-jointed; first and second joints externally 

 obliquely truncate, emarginate, for the reception of the following 



