90 K- Takahashi 



long as wide at the base, almost as long as tlic 4t]i antennal joint. Antennae very 

 short, 4-jointerl, witli a few long hairs; the orcl joint moderately expanded toward 

 the apex, witli the apical sensorinm quite small; tlie 4th almost as long as the basal 

 two joints taken together; the relative length of joints about as follows: III-17, 1 V-15. 

 Rostrum quite siiort, reaching beyond the front caxae. Abdomen wide, with some 

 ratlier long liairs. Cornicles very short. Cauda much M'ider than long, wider than 

 tlie lobe of the anal plate, constricted at the base, provided with some long bristles. 

 Anal plate bilobed, with some long bristles. TjCgs furnished with some moderate or 

 very long fine hairs; tibiae stouter than the antenna; front tibiae a little longer than 

 the antenna; tarsi not imbricated; Iiind tarsi longer than the 3rd antennal joint. 

 "Wax pores well-dcvelo]ied, large, circidar or subcircular, distributed as in 0. l<inif/crn 

 Zahnt. Head between the eyes witli two groujis of wax-pores, each group contain- 

 ing about 6 jwres. Each thoracic and abdominal segment (from the 1st to the 7th) 

 witli about 8-10 wax-pores in a circular group on the sides; the 8tli abdominal 

 segment witli numerous (about 20 ?) wax-pores in a group at the middle of tlie 

 dorsum. 



Length of body-about 1 .5 mm. 



Hont.-Oplmnenuii compotiifut^, attacking the leaf. 



Distribution.-Formosa : Kuraru, Koshun, 



A few wingless forni'^ were collected by the author on November 10, 1923. 



This ajdiis differs from O. oricntaU.-< Takah. (Aphididae of Formosa-2, p. 52) 

 in tlie following characters: 



(1) Head provided witli wax-jwres. 



(2) Horns larger. 



(3) Antennae shorter, 4-jointed, the 4th joint very sligiitly shorter than the 

 3rd. 



In 0. orinila/is Takah., the 3rd antennal joint is sometimes divided, though 

 not distinctly so, and the relative length of tlie 3rd and 4th joints is about 28: 20. 

 0. nplhmcni is easily distinguishable from 0. Inrdgcra Zehnt. by the colour of tlie 

 body, as well as by the stouter horns on the head. 



Cerataphis formosanus n. sp. 



(Pl.X,B,fig.3) 



Wingless viviparous female. 



Black, with white secretions along tiie whole margin of the body. Head fused 



with the protliorax, ou the lower side with a pair of very small tubercles 



