286 ELEMENTARY STUDIES IN INSECT LIFE 



three-jointed; organs of hearing situated in the anterior 

 tibae and also in the prosternum. 



C. Tarsi four-jointed; ovipositor (when exserted) form- 

 ing a strongly compressed, generally sword-shaped blade. 



Locustidfte. 

 ( Katydids.) 



CC. Tarsi three-jointed; ovipositor (when exserted) form- 

 ing a nearly cylindrical, straight, or occasionally up- 

 curved needle. Gri/lliddc. 



(Crickets.) 

 NEUROPTERA. 



A. With four or two wings well developed. 



B. Antennae inconspicuous, awl-shaped, short and slender. 

 C. First and second pairs of wings nearly of same length ; 



tarsi three- jointed. Libclliiliduc. 



(Dragon-Flies.) 



CC. Second pair of wings either smaller or wanting; tarsi 

 four- or five-jointed. Ephcmcridm: 



(Day-Flies.) 



BB. Antennae usually conspicuous, setiform, filiform, clavate, 

 capitate, or pectinate. 

 C. Tarsi two- or three-jointed ; wings unequal. 



D. Hind wings smaller. Psocidae. 



(Book-Lice.) 



DD. Hind wings of same size, or broader than fore wings; 

 anal area large, of simple venation, folded. 



Perlidae. 



(Stone-Flies.) 

 CC. Tarsi four-jointed; wings unequal. TcnnHidnc. 



( White Ants.) 



CCC. Tarsi five- (sometimes apparently but four-) jointed. 

 D. Hind wings with no anal space, not folded. 

 E. Mouth more or less prolonged into a beak. 



1'i/iwrjiidae. 

 (Scorpion-Flies.) 

 EE. Mouth not prolonged into a beak. 



Hcmerobidae. 

 (Lacewing-Flies.) 

 DD. Hind wings with a folded anal space. 



E. Wings reticulate. Sialidae. 



(Dobson-Flies.) 



EE. Transverse veins rather few. Phryganeidae. 



(Caddis-Flies.) 



