116 CRABS AND INSECTS. . 
Works on Neuroptera for further reference. 
“Synopsis of described Neuroptera of North America,” H. A. 
Hagen, ‘Smithsonian Miscellaneous Collections,” vol. iv, No. 1, 1862; 
“Transformations and Anatomy of Corydalus Cornutus,” Holdeman 
and Leidy, ‘“ Memoirs American Academy,” vol. iv; ‘‘ Immature State 
of the Odonata,” L. Cabot, “ Catalogue of Museum Comparative Zo- 
ology,” No. 5, 1872; ‘‘Caddis-Worms and their Metamorphoses,” 
‘“‘ Popular Science Review,” July, 1868. 
Fic. 139.—Praying mantis. 
Order III. Straight-Winged Insects (Orthoptera). 
—General Characteristics.—Insects having four straight. 
narrow, net-veined wings ; metamorphosis complete ; about 
5,000 species are known. 
