148 MISCELLANEOUS STUDIES 



42. Genus Colopha Monell 



Monell, Can. Ent., vol. 9, p. 102, 1877. Type Byrsocrypta ulmicola Fitch. 



172. Colopha ulmicola (Pitch) 



Fitch, Rept. Ins. N. Y., vol. 4, p. 63, 1858. Byrsocrypta (orig. desc.). 

 Davidson, Jour. Econ. Ent., vol. 2, p. 299, 1909 (list). 

 Patch, Maine Agr. Exp. Sta., Bull. 181, 196, 1910 (desc.). 



Record. Ulmus sp.; Stanford University (Davidson). 



Davidson recorded this species from elm at Stanford University in 

 1909. Since then it has not been found again. 



43. Genus Eriosoma Leach 



Leach, Trans. Hort. Soc. London, vol. 3, p. 54, 1820. Type Aphis lani- 

 gerum Hausman. 



Until quite recently this genus has been known as Schizoneura 

 Hartig, but as Baker 32 has pointed out, the name Eriosoma, has 

 priority. In California there are three distinct species represented, 

 with a possible fourth. One of these is known only on elm, one on 

 apple (and elm), and one on pear (and elm). 



The following key to the fall migrants is adapted partially from a 

 table of Baker and Davidson. 33 



1. Body naked except caudal segment. Distal sensoria of V and VI with fringe. 



languinosa (Hartig) 



Body with some woolly covering. Distal sensoria without fringe 2 



2. Wing veins narrow without brown margins. Ill longer than IV, V, and VI 



together lanigerum (Haus.) 



Wing veins broad with brownish margins. Ill not so long as IV, V, and VI. 



americana (Biley) 



173. Eriosoma americana (Riley) 



Eiley, TJ. S. Geol. Surv., Bull. 5, p. 4, 1879. Schizoneura (orig. desc.). 

 Clarke, Can. Ent., vol. 35, p. 248, 1903. Schizoneura (list). 

 Patch, Maine Agr. Exp. Sta., Bull. 220, p. 268, 1913. Schizoneura (desc. 

 note). 



Becords. Ulmus americana; Berkeley (Clarke); Walnut Creek, June, 1915 

 (Davidson) ; Palo Alto, May, 1915. 



This leaf-curling aphid of the American elm is found in. the San 

 Francisco Bay region, and in some cases is very abundant. In May 



32 Baker, A. C., The woolly apple aphis, U. S. Dept. Agr., Office Sec 'y, Report 

 101, pp. 11-12, 1915. 



sa Baker, A. C., and Davidson, W. M., Woolly pear aphis, Jour. Agr. Ees., 

 vol. 6, p. 358, 1916. 



