KEY TO AMERICAN INSECT GALLS 



35 



Reared from apparently unmodified branches and limbs of Salix fend- 

 ler iana . Felt 'i6f, p. 191 



Itonid. Phytophaga timberlakei Felt 



Slender twigs slightly enlarged. Felt 'o8e, p. 370 



Itonid. Phytophaga americana Felt 



Slender twigs slightly enlarged. Fig. 34. Felt 'o8e, p. 370 



Itonid. Phytophaga caulicola Felt 

 Slender twigs slightly enlarged. Felt 'i5e, p. 103 



Itonid. Rhabdophaga caulicola Felt 

 Slender twigs slightly enlarged. Fig. 35. Felt 'oge, p. 290 



Itonid. Sackenomyia packardi Felt 

 Slender twigs slightly enlarged. Fig. 36. Ckll. '04, p. 155 



Itonid. Sackenomyia porterae Ckll. 

 Twigs probably hardly enlarged. Felt 'o8e, p. 371 



Itonid. Phytophaga perocculta Ckll. 



Fig. 39. Willow potato gall, 

 Rhabdophaga batatus 

 Walsh. Typical enlargement. (Au- 

 thor's illustration) 



Fig. 40. Scarred wil- 

 low gall, Phyto- 

 phaga tumidosae 

 Felt. (Original) 



Inconspicuous, knot or twig enlargement. Felt 'oSe, p. 358 



Itonid. Phytophaga latipennis Felt 

 Twig uniformly enlarged, gall 5 to 7 cm long. Fig. 37. Felt '156, p. 109 



Itonid. Rhabdophaga podagrae Felt 

 Gall similar to above, cells in wood. Fig. 38. Felt '156, p. no 



Itonid. Rhabdophaga cornuta Walsh 

 Gradual enlargement of the twig, usually extending partly around it and several- 

 near each other, polythalamous, length i to 3 cm. Rohw. '09, p. 15 



Hym. Euura nodus Walsh 

 Gradual twig enlargement, length 30 mm, diameter 7 to 10 mm, on S. 1 u t e o - 

 sericea. Rohw. '09, p. 16 



Hym. Euura macgillivrayi Rohw. 



