GALL APHIDS OF THE ELM. 235 



1904. Schico7ieura amcricana, Cooley. loth Ann. Rept. ]\Iont. Agr. 



Exp. Sta. pp. 43-45. Discussion of work. Life history with 

 reference to Riley. 



1905. Scliisoiieura arnericana, Cook. The Insect Galls of Indiana, p. 



851 — brief mention with reference. (From 29th Ann. Rept. 



of the Dept. of Geol. and Nat. Resources of Indiana 1904, pp. 



801-867). 

 1905. ScJiizoneura amcricana, Felt. N. Y. St. Mus. Memoir 8: pp. 172, 



177-178. Description of leaf curl, and life history adapted 



from Riley. 

 1909. ScJiizonciira ulvii (arnericana), Gillette. Journ. Ec. Ent. Oct. 



Fig. 16. Antenna. 



SCHIZONEURA RILEYI 



Eriosoma iilnii Riley. 



(Found clustered in woolly bunch'es on trunk and branches of 

 young elms — Uhnus arnericana, causing knotty growth. Fig. 

 163). 



DESCRIPTIVie. 



f generation, apterons viviparous form. Head, an- 

 tenna, and thorax light brown. Legs light brown with dusky 

 points. Abdomen brown and very flocculent. Antennae 6-jointed, 

 III, 0.22 mm. ; IV, 0.08 mm. ; V, 0.09 mm. ; VI, o.i mm. Total 

 body length 2 mm Color description from live mature speci- 

 mens examined August 4, 1906. Measurements from 'balsam 

 moimts. 



Habitat, — Closely packed in woolly bunches on trunk and 

 branches of young elm, causing knotty growth of wood. Maine 

 collection numbers, — Aphid 69-05, Aphid 95-06, Aphid 89-08. 



f generation, zvinged viviparous form. Head and eyes 



black. Antenna* black, 6-jointed, III, 0.4 mm. -0.5 mm. ; IV, 

 0.1 1 mm. -0.135 mm.; V, 0.13 mm.; VI, 0.09 mm.-o.ii mm. 

 Number of annulations. III, 17-22; IV, 4-6; V, 7-9; VI, 3-4. 

 Prothorax and thorax black. Wing expanse, 6.25 mm.-6.50 

 mm. A^eins slender and light brown. Shape of wings and 

 trend and extent of veins as in amcricana (Fig. 157). Femora 

 dusky at distal part, tibia very pale, tarsus dark. xVbdomen 

 dark brown and flocculent. Color description from live speci- 



*For comparison the antenna of Scluzoiicura amcricana of Maine col- 

 lection 5-09 — July I, 1909, is given: III, 0.4 mm. -0.5 mm.; IV, 0.18 mm.- 

 0.19 mm.; V, 0.15 mm. -0. 165 mm.; VI, 0,13 nun. -o. 14 mm. Annula- 

 tions III, 24-30; IV, 8-11; V, 4-7; \J, with irregular ridge at base of 

 spur. Wing expanse 6.5 mm. -7.0 mm. 



