APHIDID.!-] OF FORMOSA. H 



Auteuure very loDg aud slender, ulir.ost witliunt Jjuirs ; the ord joint prcivided 

 Avitli about 30 rather small, scunowbat prutrndiug circular seusoria arranged almost 

 in a row over nearlj- the whole length ; the 4th somewhat imbricated, lacking 

 sensoria ; the relative length of joints about as follows: III — 147, IV — 107, 

 \ — 81, VI — 28 -f- V Al.>domiual segments provided with many short seta> 

 arranged in a transverse row. Cornicles cj-lindrical, very long and slender, 

 imbricated, a little reticulated at the tip, somewhat dilated at the base, a 

 little mure than twice as long as the cauda, and a little shorter than the 4tli 

 anteunal joint. Cauda eusiform, pjro-\ided Avith 3 pairs of long lateral bristles 

 and an apical one. Ihe 1st and ■2ud obliques on the fore wing rather stout. 

 Legs very long and slender, proAided with many rather long normal sut;c ; 

 tarsi rather shoit. 



Length of body — about 2.5 mm. Curnicle — about O.G uim. 



Host. — Cirsium Japonicum. 



Distribution — Formosa ; Taihoku ; Ja]:an : Tokyo. 



Macrosiphum debilis n. sp. 



(I'l. IV, A, figs. 2-4) 



Wingless viviparous female. 



Dirty green, somewhat pinkish. Eyes red. The 3rd and 4th anteunal 

 ji'ints pale brown, which Hack apices; the 5th and 6th black. Cornicles 

 black. Cauda green, slightly dusky. Legs i^ale brown, \vith the apices of 

 femora and tibire, and tarsi lilack. Body with seme rather short stout setaj 

 which are son:ewhat knobljed. Frontal tubercles not convex on the inner side. 



Autenuffi slender, A\ith some short capitate hairs, the 3rd joint provided 

 Aiith 8 — 11 small circular seusoria not arranged in a row on the liasal hrdf; 

 the 4th somewhat imbricated, lacking seusoria ; tha relative length of joints as 

 follows: III— 65, r\'— 55, V— 44, VI— 74 (17 + 57). Kostrnm reaching the 

 middle coxa\ Cornicles cylindricrd, st^ut, dilated at the base, tapering, im- 

 bricated, reticulated almost on the distal half, about 4 times as long as wide, 

 almost reaching the base of the cauda, almost as Ling as or a little longer 

 than the 4th anteunal joint. C^auda ensiform, a little shorter than the cornicle, 

 with 3 pairs of long lateral Inistles. Legs lung and slender, with many 



