\liliiiliil;ii' ul' Formosa. — 3. 27 



large ciri'iilar sensoria arranged almost in a single row over tjie whole length except 

 at the liase and the tip, with a lew stout hairs whicli are nuirh shorter tlian tliose on 

 the head; the 4th iniliricatcd, without sensoria, liut with some short setae; tlie relative 

 length of joints about us follows: III-107, IV-90, V-77, Vr-170 (£0+140). 



Rostrum readiiiig the liind eoxae. Venation normal; tlie 1st and 2nd ol>Ii- 

 (pus on tlic front wing stout; hind wings with 2 almost p.irallcl oliliipies; hooklcts 

 2. Al)domen jjrovided witii some long slout hairs, wliieh are almost as long 

 as those on the head and seareely laioblwd, arranged in a transverse row on the 

 dorsum of the segment. Cornicles cylindrical, very long and slender, very slightly 

 tai>eriug, not dilated at the base, srarotdy curved, imbricated, roughly reticulated at 

 th(^ tip, very slighty shorter than the ;»rd antcnmil joint. Cauda long and slender, 

 ])rovidcd witli •"> ]).urs of lateral and an apical very long bristle. 



Legs very long and slender; tiliiac provided with many rather long s_tai'; taisi 

 irnl)rie:\tcd; hind tarsi shorter than tiie basj of the las; antennal joint. 

 Length of liody-alxiut 1.7 inin. Antenna about 2. o mm. 

 Fore wing-alwut 2.7 mm. Cornicl(!-ai)out 0.5 mm. 



The young and grown nymphs, as well as the winged and wingless viviparous 

 fcnialcs, are ]irovided with a few small circular sensoria on the trochanter and the 

 liasa.l |iart of the femur. 



ITost.-7-'r///A/ iirijiii'iiiliK L., attacking the lower sidi.' of the leaf. 



Uistriliuti'iii. Formos.i : Shinten near Tailioku. 



^Fany wiiig-d and wingless viviparous females were collected on Mav 13, 

 lit2;'., by the author. 



Macrosiphum formosanum Takali. 

 Aphididae of Formosa, part 1, )>. G (1921) and p.irt 2, p. 74 (1923). 



Brachyplcrous vivijiarous female. 

 l)iners I'rom the wingless viviparous female in the following points: 



1. Wings of a nyiiiplial character iirescnt. 



2. Head with 3 very small ocelli. 



:>. 'I'liiira.x somewhat developed, l)ut not so well as that of the winged form. 



The relative length of tlie antennal joints is about as follows: III-184, IV- 

 40, V 10, VM30 (20+110). 



A brachypterous female was prodiici'd in 3Iay, and another one in August, 

 1923, by the wingless form in my laboratory at Tuihoku. 



Myzus tropicalis Takah. 



