IMatsi MuuA : XiAv Aphidinak oi.' Japan. n 



about <S small .sensoria on the upper surface, the 4th and 5th subequal, the 3rd 

 somewhat longer than the 4th and 5th taken together; anterhinarial about 4 times 

 as long'as the postrhinarial. Stigma at the posterior margin somewhat infuscated, 

 radial vein arising exactly at the midde of the stigma, 2nd furcal quite near the 

 apex. Cauda small. 



Length — 1.5-2.5 mm.; exp. 7-9 mm.; antennae 1.5 mm.; cornicles 0.25 mm. 

 Cauda 0.09 mm. 

 Apterous viviparous female — Differs from the wingerl viviparous female as 

 follows : 



l^ody much broader. Antennae shorter than the body, the 3rd antennal joint 

 somewhat longer than the 4th and 5th taken together, lacking distinct sensoria, 

 the 4th somewhat longer than the 5th ; anterhinarial nearly 3 \ times as long as 

 the postrhinarial. Cornicles near the apices scarcely inflated. Cauda broad, 

 conical, distinctly longer than wide. 



Length — 2-3 mm.; antennae 1.5 mm.; cornicles 0.3 mm.; cauda 0.08 mm. 

 Hab. — Hokkaido (Sapporo) ; on the 1st of August, 1917, collected b\- the 



author in tlie Botanical Garden of the Imperial Agricultural College. 

 F. P. — Pniiuis doiiarnun and P. aniericana ; when the leaves tue attacked 

 by this^Aphis, they curl downwards, changing tlie colour often to 

 crimson-red. 



2. Yezosiphum n. g. 



Somewhat resembles Siphocoryne Pass., but differs from the latter as follows: 

 The 3rd antennal joint very long, distinctly longer than the following 3 joints 

 taken together, with numerous granulous sensoria all over the surface, the 4th and 

 5th joints short and subequal ; anterhinarial somewhat longer than the postrhina- 

 rial, the latter somewhat shorter than the 5th. Cornicles short, somewhat inflated 

 in the middle. Cauda longer and broader than the cornicles, long-conical. 

 Genotype — Yezosiplmui thalicfri Mats. 



10. Yezosiphum thalictri n. sp. (PI. I. f. 4. a, b, c). 



Winged X'iviparcTi.us female — Hod>- darlv greenish brown, oblong in shape. 

 Antennae as long as the body, the 3rd joint with about 55 granulous sensoria; 



