AHX. 20 



THE APHID GENUS AMPHOROPHORA MASON 



19 



Spring Migrant on Rihes. — Antennae dark colored, somewhat 

 longer than body, tuberculate, hairs inconspicuous, shorter than 

 width of segment, I gibbous on inner side. Antennal tubercles very 

 small. Beak short, not reaching second coxae. Prothoracic tubercles 

 showing. Abdominal segments with lateral dark patches. Cornicles 

 rather short, moderately swollen, slightly imbricated at tips. Cauda 

 long, strongly constricted, with three sets of lateral hairs. 



Antennal 7neasurements 



Other measurements 



Alate viviparous female (on Sonchus). — Antennae about one-quarter 

 longer than body, dark colored, imbricated, numerous sensoria, hairs 

 shorter than width of segment, somewhat capitate. Antennal tuber- 

 cles very small. Prothoracic lateral tubercles present, a hair in front 

 of each. Abdominal segments with lateral dark spots, each spot 

 imbricated and having several hairs and usually a tubercle. The 

 spiracle shows either on or near this dark spot. A large dorsal dark 

 area above and between base of cornicles. Cornicles short, distinctly 

 swollen, the tip with about two imbrications. Cauda long, slender, 

 strongly constricted, the lateral edges above constriction showing as 

 dark colored. An occasional specimen has the cauda much broader 

 and not strongly constricted. Three sets of lateral hairs on cauda. 



