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TEXT-BOOK OF ENTOMOLOGY 



psyche). These also occur on the veins, and detached ones near 

 large one-jointed hairs, or hair-scales, said by Kellogg to be stri- 



FIG. 227. View looking down upon the 

 upper (i.e. exposed) surface of one of the large 

 scales situated on the veins of Danais plex- 

 ippus, about four days before emergence: 

 elm, chitinous pillars found in scales. A, a 

 smaller scale, a, a', sections of the scales. B, 

 leucocyte found in the larger scale. After 

 Mayer. 



Fio. 228. Scale-follicles : A, of a scale 

 of tfiilleria mt'lloiteUa : r, neck-ring. B, 

 the same of Pol/yommatus plihtax. C, 

 the same of a hair on inner edge of hind 

 wing of Lyccfnti aletfisty . After Spuler. 



ated. Kellogg has detected these scale-hairs, as he calls them, in 

 Panorpa. 



The " hair-scales " of the phylogenetically older Trichoptera cor- 

 respond to certain scales of Lepidoptera, especially the Fsychidse 



& 



Fie. 229. ^4, portion of wing of a caddis-fly (Mystacides). B, enlarged, showing the androconia 

 and hair-scales. C, a separate amlroconium. After Kellogg. 



(Spuler), variously called "plumules" (Deschamps), "battledore 

 scales," also certain minute cylindrical hairs. To these scent-scales 



