125 



GRAPE-VINE TOMATO-GALL. 



Lasioptera vitis O. S. 

 Model in wax of the abnormal growths on terminal twigs of the 

 grape, caused by the sting of a little gnat. 



GRAPE-VINE PHYLLOXERA-GALL. 



Phylloxera vastatrix Planch. 

 Model in wax of the galls produced by the leaf form of the grape 

 Phylloxera, showing their characteristic appearance and disposition on 

 the leaf. 



SOCIAL GRAPE CATERPILLAR. 



Harrisina americana Harr. 

 Twigs of grape-vine modeled in wax, showing the characteristic 

 appearance and work of the larvae and their method of feeding in 

 uniform rows on the leaf. 



THE GRAPE-SEED WEEVIL. 

 Craponius insequalis Say. 

 A bunch of grapes, showing damage to the berries by the larva? of 

 this insect; also punctures made by the female beetle in oviposition. 



THE SILKWORM. 



Bombyx (Sericaria) mori Linn. 



Enlarged model of the larva, showing its complete anatomy; the 

 muscles, nerves, trachse, viscera, the silk apparatus in its whole extent, 

 the silk-secreting gland, and the gland discovered by Auzoux, which 

 secretes a liquid, the use of which is most probably to convert the 

 silky matter into insoluble threads. In one of the prolegs may be 

 seen the muscles which move the claws and sucking disks which enable 

 the animal to walk with its true feet in the air. 



Enlarged models of the moths, male and female. In each model is 

 shown the atrophy of the digestive tube and the development of the 

 marvelous organs by which the species is perpetuated. (After Auzoux.) 



HOP PLANT-LOUSE. 



Phorodon humuli Schr. 



Unaffected Hop Plant. — A spray of hops, modeled in wax, repre- 

 senting the plant as it appears in vigorous growing condition, and free 

 from the attacks of its principal enemy, the hop plant-louse to con- 

 trast the stronger foliage and the more abundant and larger hops 

 produced by plants from which the hop louse has been eradicated by 

 the use of proper remedies. 



Affected Hop Plant. — A spray of hops modeled in wax, repre- 

 senting the vine as it appears when attacked by the hop plant-louse, 

 showing the blackening and discoloration of the leaves and the small 

 and inferior hops which are also discolored and otherwise unsuitable 

 for market. 



