i 



KEY TO AMERICAN INSECT CALLS 



121 



Thickened, green or reddish, crested, cockscomb-shaped ridges arising from 



lateral veins, length lo to 15 mm, height 8 mm. Fig. 114. Felt '06b, p. 186 



Aphid. Cockscomb elm gall, Colopha ulmicola Fitch 



Spindle-shaped, hollow gall on the upper surface of the leaf, variable in size, 



length about 15 mm, on slippery elm. Fig. 115. Felt '156, p. 58 



Aphid. Slippery elm pouch gall. Pemphigus u 1 m i f u s u s 



Walsh 



Fig. IIS. Slippery elm pouch gall. Pemphigus 

 ulmifusus Walsh. (Author' ' illustration) 



Fig. 116. Elm sack 

 gall, Tetraneura 

 lulmisacculi Patch. 

 (Author's illustration) 



Globose, subsessile, yellowish green, sometimes pink-tinted leaf gall, diameter 

 5 to 13 mm, on U. m o n t a n a. Fig. 116. Felt '156, p. 57 



Aphid. Elm sac gall, Tetraneura ulmisacculi Patch 

 Curled and twisted leaves containing numerous mealy-covered Aphids, on U. 

 americana. Felt '06b, p.' 177 



Aphid. Elm leal aphid, Schizoneura americana Ril. 

 Globose, green or yellowish gr^en, pocket galls, on U. ajm e^r i c a n a, U. 

 r a c e m o s a, U. f u 1 v a. Chadwick '08, p. 149 



Acarid. E r i o p h y e s sp. 



