Index 



Ulnus americanus (water elm), 329. 

 campestris (English elm), 324, 345, 

 346. 



Umbellularia californica (California 

 laurel), host for Rhopalosiphum 

 persicae, 331, and for Myzus cir- 

 cumflexum, 335. 



University of California, campus of, 

 new species of Aphididae from, 

 301-346. 



Veins, in Avings of insects, distribu- 

 tion of in wing-root formation, 

 32-33, 36-37, 38, 39; nature of, 

 40-42; characters in recognition 

 of: shape, 42, 43, trachea in, 43- 

 47, size of, 47, pigmentation of, 

 47—49, hairs on surface of, 49, 

 56, effect of, on pattern, 49, re- 

 lation of folds to, 50; develop- 

 ment of, 51-59 ; mechanical neces- 

 sity for, 62; alignment of, in 

 wasps, 375. 

 independent, 68-69. 

 convex and concave, 70. 

 cross, 71, 78, 79, 80, 130. 



Venation, of insects' wings, origin of 

 60-73, 85-89; mechanical theory 

 of origin of, 62, 72; methods of 

 modification of, 73-84; types of, 

 85-142. 



Vespa, 378, 390, 391, 392, 401, 403. 



Vespidae, key to subfamilies of, 379- 

 380. 



Viburnum tinus, host for Aphis pomi, 

 341. 



Vigna catjang (blaekeye bean), host 

 for Aphis medicaginis, 340. 



Wasps, masarid, taxonomy and species, 

 369-464. 



Wilson's bonnet gall-louse (Eri- 

 soma?), 345. 



Wing Veins of Insects, 1-152. 



Wings, importance of, in classifica- 

 tion, 1; origin of, 4-14, 53; need 

 for development of, 9; relation 

 of, to body, 14-20; function of, 

 in flight, 21-30; articulation of, 

 30; coordination of, 73-76; sys- 

 tem of folds of, 76-77; of wasps, 

 taxonomic characters of, 372- 

 377, 378. See also Venation; 

 Veins. 



Woodworth, C. W., 1-152. 



Woolv aphis (Eriosoma lanigera), 345, 

 346. 



Xenobonis canadensis, 237. 



Xenoneuridae, Paleozoic fossil insect, 

 venation in Avings of, 103. 



Xerophloea Adridis, 248. 



Xiphydria, 399. 



[472] 



