Aphididae of Formosa.— 3. 81 



tlian long, scarcely ou cones. 



Cauda wider tlian long, broadly rounded, not constricted. Anal plate not 

 bilobed. Legs long, furnished with many very long hairs; tarsi long; liind tarsi 

 almost as long as the 4th antennal joint. 



Length of body-about 2.7 mm. Antenna-about 0.7 mm. 



Some winged viviparous females were observed on January 14, 1924, at 

 Taihoku. 



Oregma alexanderi n. sp. 



(PI. X, B, figs. 4-5 & 12) 



Wingless viviparous female. 



Almost brownish black, with a somewhat purplish tinge, sliglitly covered with 

 powder. Antennae brownish, with the last joint black. Tibiae brownish. In speci- 

 mens treated with c.iustic potash, the head and prothorax dark brownish, meso-and 

 metathorax each with a very large dark brownish patch on the sides togetlier with 

 some very small spots, basal three abdominal segments each with a large similar 

 patch on the sides, the 4th and the following abdominal segments each with a small- 

 er similar patch on the sides, legs yellowish brownish, cornicles almost black, 

 Cauda and anal plate dusky. Body somewhat elongate oval, not depressed. Head 

 fused with the prothorax, witli some rather long hairs. Eyes composed of 3 

 facets. Horns ratlier stout, almost as long as the 1st antennal joint, sharply pointed 

 at the apex, curved upward. Antennae rather slender, 4-jointed, witii a few 

 moderate or rather long liairs; the 1st joint larger than the 2nd; tlie 3rd very 

 slightly curved, slightly exjiandcd at the apex, sometimes witli a constriction, the 

 sensorium very small; the 4th almost as long as or slightly shorter than the biisal 

 two joints taken together; the relative length of joints about as follows: III-57, 

 lV-33. Rostrum very stout, reaching the hind margin of the prothorax. Thorax 

 and abdomen furnished witli some rather long bristles. Cornicles not situated on 

 cones, very short, but very large in diameter, much larger than the wax-pore on 

 the 8th abdominal segment. Cauda much wider than long, wider than the opening 

 of the cornicle and the lobe of tlie anal plate, constricted at tlie base, with some 

 very long bristles. 



Anal plate large, deeply biloljed, with some very long bristles. Legs very 

 long; tibiae much stouter than the antenna, front tibiae about twice as long aa tlie 

 antenna; hind tibiae provided with many rather long bristles; tarsi long, not 

 imbricatttd, hind tarsi longer than the 3rd antennal joint. The 6th abdominal 



