116 



HALF nouns WITH i:n'sects. 



[Packaijd. 



find their way into the European markets, are dyed \Yith 

 Kermes. Carmine is also made from it." Manna is said to 

 be produced by the stings of the Coccus manyiiparus first 

 described by Ehrenberg, who found it at Sinai growing on 

 the tamarix. The lac insect, so valuable a commercial prod- 

 uct, is a bark louse which lives in the East Indies on the 

 Ficus religiosa. This insect, by its beak, punctures the bark 

 especially of the branches. From this puncture exudes "a 

 quantity of vegetable matter which eventually surrounds the 

 lac insect and her eggs and larvae, and produces on the 

 branch an irregular brown mass, which encircles it and 

 w^hicli when broken has a resinous aspect. This is gum lac." 

 (Lankestcr). When found on the twigs it is called stick lac, 

 but after it has been pounded, and the greater part of the 

 coloring matter extracted by water, it is called seed lac ; 

 when melted down into cakes after it has been strained and 

 formed into thin scales, lump lac and shell lac. 



The most troublesome scale insect found on cultivated 

 plants is the white scale insect or Asj^kliotus hromelioi (Fig. 

 79). The snow-white round scales crowd one fig. 7o. 

 another on the leaves of acacias, the Olea fra- 

 grans, Guidia simplex, etc. 

 On examination with the mi- 

 croscope the dead and shriv- 

 elled body of the female may Aspidiotus 

 be seen in the centre. Ifc is iJ™'«ei'«- 

 oval in form, Avith a ridge along the 

 middle, and yellowish, contrasting with 

 the snow-white thin edge of the scale, 

 the surface of which is minutely granu- 

 lated and white, as if frosted. 



The young (Fig. 80, enlarged) are 



Young of A. bromeline. ^j^j^^ ^^^^ COUVCX, with the hind edge 



simple. The segments (not all indicated in the cut) are 

 quite indistinct. Around the edge of the posterior third of 



20 



Fig. so. 



