PROC. ENT. SOC. WASH., VOL. 24, NO. 7-8, OCT.-NOV., 1922 205 



brown. Legs yellowish brown, apices of tibiae slightly dusky, tarsi blackish. 

 Body lacking capitate hairs; head provided with some short normal bristles. 

 Frontal tubercles very short, somewhat projecting on the inner side. Antennae 

 lacking hairs; the 1st joint larger than the 2d, with a short blunt tubercle on the 

 inner side, the 3d joint not imbricated, provided with 27 large oval sensoria 

 scattered over the whole length; the 4th joint somewhat imbricated, provided 

 with 14 large circular or oval sensoria scattered over the whole length; the 5th 

 joint provided with 5 large sensoria in a row over the whole length, the apical 

 sensoria large and oval, the relative length of joints as follows: 111-49, IV-29, 

 V-26, VI-67 (15 + 52). Rostrum reaching the middle legs. Subcosta provided 

 with 7 small sensoria on the distal two thirds; the 2d branch of the 3d oblique 

 rather short, hind wings with 2 almost parallel obliques; booklets 3. Cornicles 

 almost similar to those of the wingless form, moderately swollen on the distal 

 two thirds, expanded at the base, 5 times as long as wide, as long as the spur of 

 the last antennal joint, almost 4 times as long as the cauda. Cauda triangular 

 when seen from above, almost as long as wide, provided with 2 pairs of lateral 

 bristles. Legs slender, provided with many bristles; hind tarsi as long as the 

 cauda. Length of body, 2.25 mm.; fore wing, 3.4 mm.; antenna, 1.5 mm.; 

 cornicle, 0.37 mm. 



Host. Rubus sp. (Rubus fraxi nifolius?}, attacking the leaf 

 and the young shoot. 



Hab. Formosa (Kagi). Collected by the author in March, 

 1921. 



Described from specimens preserved in alcohol. 



Type. Retained by the writer. 



Trichosiphonaphis new genus. 



Wingless form. Body wide, provided with some short capitate hairs. Frontal 

 tubercles large, with a short blunt tubercle on the inner side. Antennae 6- 

 jointed, spur longer than the base, the 1st joint slightly convex on the inner side. 

 Dorsal and lateral tubercles absent. Cornicles cylindrical, somewhat swollen 

 near the apex, provided with some prominent capitate hairs. Cauda large, 

 longer than wide, somewhat constricted at the base, shorter than the cornicle. 

 Tarsi and anal plate normal. 



Winged form. Body lacking capitate hairs. Frontal tubercles very short, 

 slightly convex on the inner side. Antennal sensoria circular. The 3d oblique 

 of the front wings twice forked; hind wings with one oblique. Cornicles cylin- 

 drical, slightly swollen near the apex, provided with some bristles which are not 

 knobbed. 



Type. Myzus polygoniformosanus Takah. 



This new genus is closely related to Myzus Passerini, but 

 differs from it in the following characters. 



1. Hind wings with only one oblique. 2. Cornicles provided 

 with normal or capitate hairs. 



Trichosiphonaphis polygoniformosanus Takah. 



Myzus polygoniformosanus^ Takahashi, Aphididae of Formosa, 1, Agr. 

 Expt. St. Formosa, p. 18, pi. XIV, 1, figs. 1-3. (1921). 



