558 



the end of this time the parasites were found well established 

 on many of the plantations. 



Additional material was received from Formosa in Decem- 

 ber, 1916, from H. Sauter, arrangements for which had been 

 made months earlier before it had become certain whether the 

 Oofetrastichus would reproduce freely in the breeding cages. 

 Both this and the original material collected by Mr. Muir was 

 obtained in the vicinity of Tainan. 



The following description is based almost wholly on 

 Hawaiian-bred material, as the original specimens from For- 

 mosa were almost all utilized in the breeding cages. 



Ootetrastichus formosanus n. sp. 



This species is closely allied to O. pallid i pes Perkins from 

 Java and the male clearly runs to paUidipes in Perkins' table 

 (Bull. No. 10, Ent. Ser. Haw. Sugar Planters' Station, p. 7-8). 

 It differs from the male type of paUidipes in having the scape 

 not quite so broadly expanded and without conspicuous bristles 

 on the dorsal margin, the parapsides largely pale except 

 anteriorly (as seen in slide mounts), the mesopleura with a 

 much larger pale area, and in having the basal half of the 

 abdomen yellow without a pair of dark spots above on either 

 side. The female has the base of the abdomen distinctly 

 yellow, so that this sex runs better to O. basalis Perkins, also 

 from Java. From the t3^pe of basalis the female differs in 

 having slightly longer wings with the discal ciliation of the 

 hind pair much longer and darker, and in having the yellow 

 and metallic parts of the abdomen more sharply differentiated, 

 with the apical half more strongly metallic. Of the Australian 

 species described by Girault (Mem. Queensland Mus. 2, pp. 

 216-223) inghauiensis appears to be similar to formosanus, but 

 it is too briefly described to permit any exact comparison. 



Female. Face below antennae, cheeks and postorbital region of head, 

 thorax, except the tegulae, hind coxae and apical two-thirds of abdomen 

 deep metallic green with brassy and golden reflections; rest of face, the 

 frons and narrow area on occiput next to the eye-margins dusky yellow; 

 ocellar region of vertex and rest of occiput fuscous ; antennae pale 

 brownish yellow; eyes dark chestnut brown, and much brighter red in 



