LecaniincB. tg^ 



LECANIUM VIRIDE, Green. 

 (Plate LXIX.) 



Lecaniuni viride. Green. ' Observations on the Green Scale Bug in con- 

 nection with the Cultivation of Coffee,' 1886 : Etitoinologist s Monthly Magazine, 

 April 1889, p. 248. 



Adult 9 {fig. 2) bright pale green, with an irregular, but very distinct loop 

 of blackish spots on the middle of the dorsum (the contents of the malpighian 

 tubules).* During treatment with potash, the colour changes to dull orange. 

 Dried examples become dull fulvous, and lose the chain of dark spots. Eyes 

 conspicuous, black, close to margin. Anal scales minute, yellowish. Form 

 oval ; rounded behind, subacuminate in front ; sometimes asymmetrical, the 

 development on one side suppressed by contact with a prominent vein of the 

 leaf. Moderately convex above, more particulaily in females containing ripe 

 ova. Margin very thin. Skin soft ; never strongly chitinised. In old indi- 

 viduals the dorsum is almost smooth ; but, before the body becomes tense with 

 eggs, a slight median longitudinal, and two transverse ridges are noticeable, 

 the latter above the stigmatic areas. Above the abdomen are three series of 

 shallow depressions on each side of median ridge, defined by indistinct trans- 

 verse and longitudinal ridges. Stigmatic clefts small and inconspicuous. 

 Stigmatic spines 3 : {fig. 4) ; stout, pointed ; the median one twice as long as 

 the others and curved at the extremity. Anal cleft from one-sixth to one-fifth 

 total length. Margin with short curved hairs, the extremities divided into 

 several points Ifig. 5), set at rather long intervals. Submarginal tubercles, three 

 or four on each side Antenna {fig. 7), seven-jointed ; third and fourth longest, 

 subequal ; seventh nearly equal to previous two together. Antennal formula : 

 (3, 4), (I, 2, 7)> (5, 6) ; or 4, 3, (i, 2, 7), (5, 6) ; or 3, 4, (i, 2, 7), (5, 6) ; sometimes 

 an incomplete division on the fourth joint. Legs well developed, moderately 

 stout ; claw stout, curved ; ungual digitules broad and spatulate, extending 

 well beyond claw ; tarsal digitules long and slender, dilated at extremity, 

 extending beyond unguals {fig. 3). Scales of anal operculum {fig. 6), tri- 

 angular ; base shortest, concave ; inner edge longest, approximately straight ; 

 outer edge slightly shorter than inner, convex. Anal ring with eight hairs, two 

 of them much more slender than the remainder. A scattered arch of circular 

 wax glands (with multilocular orifices, as in Diaspidina) enclosing the genital 

 orifice. Derm {fig. 4) with large scattered — rather indefinite — round or 

 broadly oval translucent spots. These spots are rather difficult to demon- 

 strate, and can only be made out in a good preparation. Length 2.50 to 



* The dark colour seen in the malpighian tubes is not due to any real pigmentary matter, 

 but is partly opiical, resulting from diffraction through the mass of minute greenish yellow 

 circular bodies that distend the tubes at intervals. With higher magnification the colour fades, 

 first to dull olive green and then to greenish yellow. Under pressure, which thins out the mass, 

 the same disappearance of colour is observed. 



