252 laoicm takaiiasih : 



A few wiuglcss vivi'iKiruiLS fejiiiilcs ■were collet-ted liy Mi\ Isliida in Jiiuury, 

 1917, at Shiukwa, Formosa. 



Dryopeia hirsuta l>aker. 



Host plant. — Or>/zn .sulivii, attacking tlie rodt. 



Somt! wiiigkss vivi})aroiis feroidos were collected on ^lan-li 20, 191-1, at 

 Tainan, l>y Mr. Sawada. 



General summary of principal results. 



(Host plants) 



1. From Formosa more tluiu 3500 species of plants have Ixjeu recorded, 

 of wliicli alx)ut "200 are at present known t;) lie ftxl upon by apliids in 

 Fi )rmo3n. 



2. Gall-produfing sixx-ies in Formosa are Nurudcct sidraii Mtits, Aatcyopteri/x 

 st iiracopliila Kju's, and Adegoptenjx slyracicolu Takali. These species leave the 

 gidls and migrate to nnltuowu plants. 



3. The life-histories of Ainphoropliora mnjndm (I'^^sig ot Knw.), Askijnp- 

 fi i-)/x distiifolke Takah. and Nlppddchnns pirl Mats., wliieli have tlu; luxbit of 

 alternating hosts, are known in detail. 



4. Ne:u" Taihoku, Rh/puloHiphuin ni/tiiph uce L.) inluiliits various aquatic 

 ]ilaut3 all tilt! yi:ar, without alti:vuatuig hosts, and is rarely foimd on PruriKS 

 comnnmis. Ilyaloplcrus pruni (Fal .), near Tokyo, feeds on Phrwjmites communis 

 and Prwtus spp. during the suimner and sjxinds the winter only on Pntmis »pp., 

 hut near Taihi)ku the uiscK't is found on PJirwjm'des communis tlu'oughout the 

 year and is aLso seen on Pruum spp. at tunes. 



(Season when the iiLsect is scarce) 



]\Liny s^xHiies are reduced in iiumlxjrs during the summer when the tender 

 ]) )rtious of the hosis l)e<wme scarce or their leaves become hard. 



(NA'iuged viviparous female) 



Tlie winged forms of Macrosiphnm /ormosamim Takah., Macrosiphuin 

 f/ohonis Milts., Myzns pr.rsiccB (^Sulz.), Rliopilosiplaim pseuddirassicCB (Davis), 

 ToKoptera auranUi (Bn'er), Aphis spp., U'/aloptcrus pruni (Fab.), NcoplujUtphis 

 p^xhjcarpi Takah., etc. are common in Formosa, as in Jajjan, and ntiar Tailioku 



