358 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



Klcy to Species of Cnemodon 

 I. Males 



1. Middle coxae and hind trochanters without processes unicolor 

 Middle coxae with slender process 2 



2. Hind trochanters without the usual process 16 

 Hind trochanters with long or short process 3 



3. Venter of fourth segment with spur or tubercle on basal and 



apical thirds 13 



Venter of fourth segment without spurs 4 



4. Process on hind trochanters moderately short; third antennal 



joint broader than long; a short rather stout white pilose 

 species cevelata 



Process on hind trochanters long and slender; third antennal joint 



not broader than long; neater appearing species 5 



5. Hind coxae without a spur, often with a tubercle on the outer end 8 

 Hind coxae with short sharp spur on outer end 6 



6. Coxal spur small, slender, directed towards the femora (often 



difficult to discern because of the pile) lovetti 



Coxal spur directed outwards, conspicuous 7 



7. Face whitish pilose, at least in part, (eastern) coxalis 

 Face and vertical triangle entirely black pilose rita 



8. Venter of third segment carinate at apex 10 

 Venter of third segment not at all carinate 9 



9. Face entirely black pilose; abdomen inflated, slender elongata 

 Face white pilose in middle; abdomen not inflated; second segment 



of middle tarsi almost simple calcarata 



10. Wings pellucid hyaline; face entirely whitish pilose placida 

 Wings cinereous hyaline 11 



11. Venter of fourth segment carinate at its immediate base 12 

 Venter of fourth segment simple, not even rugose pistkoides 



12. Middle tibiae produced from about the basal quarter, (western) auripleura 

 Middle tibiae produced gradually from the base, (eastern) carinata 



13. Venter of fourth segment with tubercle on apical third 14 

 Venter of fourth segment with spur on apical third 15 



14. Tubercle on apical third considerably pilose; venter of third seg- 



ment simple along carinate area ontarioensis 



Tubercle larger, somewhat spurdike; venter of third segment 



rugose along carinate area trochanlerata 



15. Wings evenly infuscated, (smaller) venteris 

 Wings with brownish cloud beyond the middle m verm a 



16. Squamae grayish fringed with cinereous pile squamuhr 

 Squamae black or brown fringed with brown pile 17 



17. Length about 8 mm: arista as long as the antennae longiseta 

 Length under 7 mm: arista scarcely longer than third antennal 



joint; anterior legs considerably yellow intermedia 



II. Females 



1. Middle tibiae not rounded in front See IJeringia 

 Middle tibiae rounded in front 2 



2. Hind coxae with a sharply pointed tubercle at outer end; pile of the 



venter depressed 12 



Hind coxae with rounded tubercle or none 3 



3. Third antennal joint clearly as broad as long, wings cinereous 



hyaline corvallis 



Third joint at least slightly longer than broad 4 



4. Wings purely hyaline, (western) 5 

 Wings cinereous or brownish hyaline 6 



5. Last section of fourth vein distinctly sinuous sinuosa 

 Last section of fourth vein nearly straight placida 



6. Pile of venter appressed or sub-appressed 7 



