MaTSI MUKA : Nl.U ArillDlNAl^ Ol- Japam. 7 



about 8 small sensoria on the upper surface, the 4th and 5th suhequal, the ^rd 

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

 as longas the postrhinarial. Stigma at the posterior margin somewhat infuscated, 

 radial vein arising exactly at the middc of the stigma, 2nd furcal (|nite near tiie 

 ajiex. Cauda small. 



Length — 1.5-2.5 mm.; exp. j-cj mm.; antennae 1.5 mm.: cornicles 0.25 mm. 

 Cauda 0.09 mm. 

 Apterous \iviparous female — iJiffers from the winged \ivi]iarous female as 

 follows : 



15ody much broader. Antennae shorter than the body, tlie 3rd antennal joint 

 somewhat longer than the 4th and 51h taken together, lacking tlistinct sensoria, 

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

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

 conical, distinctK' longer than wide. 



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

 Hab. — Hokkaido (Sapporo) ; on the ist of August, 1917, collected by the 



author in the Botanical Garderi of the Imperial Agricultmal College. 

 F. P. — Piiinus doiianuin and P. anicricana ; when the leaves ;ure attacked 

 by this^A[5his, the)' cinl downwards, changing the colour often to 

 crimson-red. 



2. Yezosiphum n. g. 



Somewhat resembles Siphocorvnc I'ass., 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 siu'face, 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 bro.ider than the cornicles, long-conical. 

 Genotype — Yezosiphiiiii thalictn Mats. 



10. Yezosiphum thalictri "■ sj). (PI. L f 4. a, b, c). 



Winged \'i\-ii)aro.us female^Hod\' <larl< greenish brown, oblong in shape. 

 Antennae as long as the body, the 3r<l joint with about 55 granulous sensoria; 



