376 DactylopiincB. 



almost completely concealed by a close covering of white mealy powder ; there 

 is, usually, however, a median and sometimes a lateral stripe partially free from 

 the secretion, revealing the true colour of the insect. The venter is only thinly 

 dusted with mealy powder. There is a complete marginal series of thirty-four 

 short, stout, white, waxy tassels, subequal in length, though rather stouter on 

 the abdominal segments. Between the last pair of tassels is a pair of small 

 ligulate processes of a denser and smoother wax, proceeding from the anal 

 orifice. Form broadly oval ; convex above, flattish below, with the segments 

 more or less tumescent. Antenna {fig. 7) eight-jointed ; eighth considerably 

 longer than any of the others ; second and third elongate, approximately equal ; 

 the fourth and seventh subequal. Limbs '\fig- 6) comparatively slender ; tarsus 

 approximately half the length of the tibia ; the tibia and tarsus together 

 approximately equal to femur and trochanter. Foot with slender digitules ; 

 the apices of the tarsals minutely knobbed, those of the unguals slightly dilated. 

 Margin of body with a series of ceriferous tracts in positions corresponding 

 with the waxy tassels. Each tract bears a pair of sharply pointed spines (see 

 fig. 4), two or three hairs and a scattered group of minute circular pores which 

 are of the same size as those on the rest of the derm. It is noticeable that 

 there are thirty-six of these tracts, though the number of apparent marginal 

 tassels is thirty-four only. Two of the tracts are situated close together on the 

 frons, and probably give rise to a single compound tassel. There are the usual 

 larger circular pores on the venter, extending across the genital area. Posterior 

 extremity {fig. 4) with slightly prominent anal lobes, each surmounted by a 

 stout caudal seta. Anal ring with six setae, which are slightly more than half 

 the length of the caudal setae. Length of Ceylon examples averaging 2'6 mm., 

 ranging from 175 to 4 mm. 



Adult male {fig. 10) dull brown, thinly powdered with white meal, except the 

 median sternal plate on the thorax, which is smoothed and polished. Caudal 

 filaments white, approximately as long as the body. Wings greyish, highly 

 iridescent. Antenna {fig. 13) ten-jointed, hairy; second joint dilated; third 

 and tenth longest ; a pair of fine knobbed hairs at apex of tenth (seeyf^-. 14). 

 Ocelli prominent, black : two on upper and two on under surface of head (see 

 figs. 10 and 11). Rudimentary eyes minute, black, lateral. Limbs slender: 

 tarsus about one-third the length of the tibia ; claw long and slender. Length 

 o*75 mm. Both apterous and micropterous forms of the male are occasionally 

 produced. 



Young larva pinkish yellow, thickly dusted with white meal. Eggs honey 

 yellow. 



On Coffee, Cacao, Citrus, Cinchona, Anona, Loranthus, Ipomea and numerous 

 other plants. Widely distributed throughout the Island. A cosmopolitan 

 species, and a common greenhouse pest in Europe. 



Living examples of this species are readily distinguishable from Ps. longi- 

 spinus (which occurs in similar situations) by the shorter and stouter fringe of 

 waxy tassels. But dried examples (which have usually lost their appendages) 

 are not so easily separated. The following microscopical points may be relied 

 upon, 



Ps. citri : Thirty-six marginal ceriferous tracts ; spines on all the tracts of 

 equal diameter ; caudal setae much longer than those of the anal ring ; tarsus 

 approximately half the length of the tibia. 



Ps. longispinus : Thirty-four marginal ceriferous tracts; spines of the ter- 



