June, '13] 



PATCH: TWO ELM LEAF APHIDES 



317 



Fig. 3. 1 and 2 Schizoneura ulmi of Europe, fundatrigenia, migrant from elm leaf, 

 collected in California; 3 and 4 S. lanigera, fundatrigenia, migrant from elm leaf, 

 no. 9-12, winged progenitors of 9-12 sub. 1 ; 5 and 6 S. lanigera, sexuparse-migi'ant 

 from apple bark, no. 9-12 sub. 1, cage reared descendants of 9-12; 7 and 8*S'. lanigeraf 

 pupa just before molt; (Figures 1, 3, 5, 7 are drawn to the same scale and figures 2, 

 4, 6, 8 are drawn to the same scale.) 



annular and like the others, or, in many cases, variously modified and 

 spread much like the terminal sensorium of VI. In the apterous forms 

 and in the nymphal stages a circular terminal sensorium exists on both 

 V and VI but these are lost in the winged form with the pupal molt, 



That two elm leaf curling species of Schizoneura occur in other 

 countries is certainly more than suggested by the figures of "ulmi" 

 by Kessler (1878), Buckton (1881), Okajima (1908), Tullgren (1909), 

 and Theobald (1912). The clue as to Avhich one of these migrates to 

 Rihes is sufficiently indicated by the figures of fodiens by Buckton, 

 Tullgren and Theobald. 



That the second elm leaf curling species of other countries is lanigera^ 



