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NOTES ON COCCID-INFESTING CHALCIDOIDEA— I. 



By James Waterston, B.D., B.Sc, 

 Imperial Bureau of Entomology. 



Amongst some insects bred this year from Lecanium viride on coffee in Mauritius, 

 and forwarded to the Imperial Bureau of Entomolog}^ for identification by 

 M. d'Emmerez de Charmoy, were two species of Chalcids belonging to the genera 

 Diver sinervus, Silv. (1915) and Tetrastichus, Hal. (1843) respectively. The former, 

 which appears to differ considerably from the genotype, is here described as a new- 

 species ; the latter so closely agrees ■s\'ith Tetrastichus sicarius, Silv., that I have not 

 thought it advisable to propose a new name. My best thanks are due to Professor 

 Silvestri for his kindness in examining preparations of both species. 



Diversinervus silvestrii, sp. nov. 



A clear yellowish or honey-coloured species. The antennae and legs colourless in 

 the main, except for a faint browning of the last joint of the club, the dorsal edge of 

 the pedicel, narrowly on the dorsal edge and more broadly ventrally on the scape. 

 The whole head, the apical half of the mandibles and the stipes brownish, a very faint 

 brown spot near the apex of the mid femur on the underside and another corresponding 

 to it on the same aspect of the tibiae near the base. Knees of the mid legs narrowly 

 tinged with brown. On the hind legs is a moderately broad superior dark streak on 

 the femur, and the tibia is brown apically and dorsally but without colour ventrally 

 from before the apex to the base. Wings with the veins yellowish ; the membrane 

 tinted, obscurely clouded medianly, the basal triangle, an indefinite posterior spot at 

 about two-thirds from the base along the hind margin, and round the apical margin 

 more hyahne. The follo^ving regions of the thorax and abdomen are darker : — 

 the posterior third of the mesonotum, the scutellum along the sides and towards the 

 apex, the meso-pleurae posteriorly, the sides of the propodeon, the first tergite in 

 front, and round about the stylets and the apex of the abdomen. The dark regions 

 on the head and abdomen have in life a cupreous or violaceous metallic lustre. 



Head in profile triangular, from the vertical aspect widely parabohc anteriorly, 

 with a slightly concave ridged occipital edge (length to breadth about 9 : 14), a little 

 wider than the thorax, distinctly wider than the abdomen and half as long as the latter 

 together with the projecting part of the o\'ipo8itor, and as long as the sum of the 

 scutellum, metanotum and propodeon. Along each orbit (from occiput to gena) are 

 placed about eighteen short recurved bristles. Between the orbits (which diverge 

 anteriorly) and dividing the area into three approximately equal strips are two rows 

 of bristles (6-7 : 6-7). Lateral oceUi touching the orbits, the anterior ocellus being 

 at the apex of an obtuse-angled triangle whose median is about one-sixth of the length 

 of the head. Behind each posterior ocellus is a long stout bristle and between this 

 pair and the occipital edge are four bristles (2 : 2) and about the same number in each 

 angle formed by the edge and the orbit. Occiput distinctly concave. Frontal 



