729 



Vayssiere, on lingua of Ephemera, 73. 



Veins of wings, 121, 144. 



Velum penis, 181. 



Venomous glands, 358. 



Vent, 319. 



Ventrieulus, 314. 



Vermipsylla, tongue of, 77. 



Verson, on serially arranged dermal 



glands, 3(56 ; vestigial stigmata, 460. 

 Vesicles, air, 456 : use of, 457; frontal, 



(L'l : of head of semi-pupal fly, 077. 

 Vespa crabro, 217 ; olfactory organs of, 



276. 



Vessel, dorsal, 397; urinary, 316, 348. 

 Vestigial trachea?, 460. 

 Viallauos, on brain, 231 ; head segments, 



51. 

 Vision, mode of, by compound eyes, 256; 



by simple eyes, 255. 

 Vitelline membrane, 520. 

 Viviparous insects, 515. 

 Volucella, thorax of, 91. 

 Vosseler, on foatid glands, 369. 



Wagner, on the circulation, 419. 

 Walking, mechanics of, 103, 106. 

 Walter, on epipharynx of moths, 44 ; on 



hypopharynx of moths, 75. 

 Wasps, taste-organs of, 277, 286. 

 Wax, of butterfly, 364; of caterpillar, 



364 ; of saw-fly larva, 364. 

 Wax-glands, 361, 364. 

 Weevil, embryology of, 538; bean and 



pea, hypermetamorphosis of, 700. 

 Weismann's discovery of imaginal buds, 



5!t'.. 6-13, (550; on formation of imago, 



67 ; vesicle of semipupal fly, 677 ; on 



tracheae, 434 ; on origin of trachea;, 447 ; 



on origin of wings, 127, 129; theory of 



histolysis, 643. 

 West, Tuffen, on feet of fly, etc., 100; on 



walking, 99. 



Westwood, on head of Hymenoptera, 55. 

 Wheeler, on embryonic abdominal ap- 



pendages, 550; on the homologies of 

 the ovipositor, 167; homology and 

 primitive number of urinary tubes, 354, 

 355; on ojnocytes, 423; on pleuropodia, 

 476, 550, 551; on the premandibular 

 segment, 51; on structure of chorion, 

 521. 



Wielowiejski, on blood tissue, 408; egg- 

 tubes, 502 ; fat-body, 419 ; phosphor- 

 escence, 424; tracheae and their end- 

 ings, 43(5. 



Williston, on anal glands, 372. 



Will, on organs of taste, 282. 



Wing-buds, or discs, 127, 129; rods, 146; 

 sheaths, 124. 



Wingless insects, 598. 



Wings, 120; buds of, 664: cells, 121; cir- 

 culation of blood in, 410; development 

 of tracheae of, 144 ; development of 

 veins of, 144 ; embryonic development 

 of, 126; folding of, 154, 15(5: imaginal 

 buds of, 653; mechanism of, 153, 15(J; 

 origin of, 138; primitive origin of, 137 : 

 as respiratory organs, 461 ; rudimen- 

 tary, ground-membrane of, 136 ; spread- 

 ing of, 155 ; theory of, 144 ; tracheae in, 

 122 ; veins of, 121. 



Wistinghausen, von, on tracheal endings, 

 436, 447. 



Witlaczil, on honey dew, 364. 



Wood-Mason, on gills of Paraponyx, 470 : 

 on Scolopendrella, 19, 22. 



Xiphidium, embryo of, 534; indusium 

 of, 534, 535. 



Yersin, on results of section of commis- 

 sures, 245. 



Yolk, amount of, 524, 529; membrane, 

 520; segmentation of, 526; cells, 562; 

 ridge, median, 563. 



Zaitha, 431 ; pleuropodia of, 551. 

 Zone, annular, 653. 



