SOUTH AFEICAN COCCID^. 249 



haps the most extraordinary coccid I ever saw ; it reminds one a 

 little of Icerya koebelei, Maskell, but in that insect the erect pro- 

 cess is of wax. It may be that the spine serves to prevent the 

 birds from swallowing the insect, while its extreme toughness 

 would make it hard to peck open. 



Tachardia, Blanchard (Lac Insects). 



This genus contains some very diverse elements, which will 

 no doubt eventually be treated as genera. We may for the 

 present recognize three subgenera : — 



(1). Tachardia proper. Type, T. lacca, the East Indian 

 commercial lac. Female very elongated, vasiform ; the in- 

 dividuals enclosed in masses of lac surrounding the twigs, never 

 separate. I know of only one species of this group. 



(2). Tachardiella, subg. nov. — Type, T. cornuta, Gkll. Female 

 more or less globular ; individuals often separate. This includes 

 the species of America and Australia. 



(3). Tachardina, subg. nov. — Type, T. albida, with the cha- 

 racters given below. 



Tachardia albida, n. sp. 



Forming smooth yellowish-white masses on the twigs ; the extremely 

 dense and hard lac of the several individuals running together ; masses 

 up to 10 millim. diam., and 30 in length. The individuals are marked 

 externally by orange patches, each presenting a small corrugated or 

 segmented ridge, and an aperture. Cavities for females globular to 

 subpyriform. Male scales of the usual elongated form, red, with a 

 very short dorsal segmented ridge, about one-third of total length 

 of scale. 



2 . After boiling in liquor potassse globular, giving a very fine 

 crimson colour. Skin after boiling transparent, truncate and caudal 

 processes remaining ferruginous. Mounted female on slide about 

 5 millim. diameter. Truncate processes (or "lac tubes") very short, 

 orifices very small and numerous. Spine apparently absent. Caudal 

 process peculiar ; transversely oblong or subreniform, with a deep 

 posterior notch, on each side of which are two lobules ; lateral hind 

 margins bearing a sharp spine ; surface finely reticulated ; anal ring 

 hidden, only the ends of the numerous bristles projecting. Spiracles 

 large and well-developed. Mouth-parts well-developed, but small, 

 about 135 Id. broad ; " lobes oraux " (as figured by Targioni-Tozzetti in 

 T. lacca) very large. 



Larva in female fusiform, narrow, tapering posteriorly, about 560 jt* 

 long and 240 broad ; caudal bristles very long. 



Hab. On Mimosa, Verulam, Natal (Fuller, 5). A very 

 peculiar species ; the first white lac I have seen. 



Chionaspis retigera, n. sp. 

 Scales crowded on twigs ; white, the exuviae orange-brown. $ . 

 Scale mytiUform, about 1| millim. long, straight or curved, very con- 

 vex, the transverse growth-lines rather conspicuous ; second skin 



