216 



NATURAL HISTORY OF ARTHROPODS. 



Fig. 293. 



- Ltcanium, upper and under 

 surfaces. 



and it is equally abundant upon oranges and a few otlier plants in the south of 

 Europe. 



The female scale is wax-yellow, darker upon the disk, of a long oval shape, smooth 

 and shining, rather flat, with a few scattered punctures on the back, the antennse seven- 

 jointed, the fourth and seventh joints nearly equal in 

 length, and the last segment of the aljdomen very small 

 and furnished with six long, stout bristles. It is also 

 viviparous. The male has not yet been discovered, 

 although the species has been widely known ever since 

 the time of Linnteus. It is the commonest and most 

 extensively distributed form of tliis group, being known 

 wherever civilized man has introduced plant-houses. 

 The full grown scale is about one-eighth of an inch in 

 length, and when dried becomes wrinkled along the 

 margins, and rests very closely in contact with the surface of the leaf. 



Besides those which are hurtful to- trees, there are others of great value 

 to commerce and the arts. The Carteria lacca of India yields the lac which is melted 

 into cakes and small sticks ready to be sold in the stores, and is employed in making 

 v-arnishes, sealing wax, water-proof surfaces, dyeing, etc. It is the puncture of the female 

 which causes this resinous substance to exude from the twigs, and this, after having 

 been collected from the banyan and other trees upon which the insect lives, is selected, 

 pounded, and the mixed coloring matter extracted by water. It is also melted, strained, 

 and formed into thin flakes or thick masses. This important insect which secretes an 

 exquisite carmine lake, is the veriest pigmy of its group, being no more than the one 

 thirty-sixth of an inch in length when full grown ; but it appears in vast numbers upon 

 the trees in the province of Bengal, as also in Siam, Assam, Malabar, etc., and is 

 thence exported to all parts of the world. The body of the dried female is red,- with 

 very hairy six-jointed antenna?, four eyes, and no ocelli. The legs remain quite dis- 

 tinct, are stout and hairy, with the tibias one-third longer than the thighs. To avoid 

 contact with the resinous secretion caused by its j)uncture the insect is enclosed in a 

 kind of woody gall, of form varying with the age and sex. That of the female apjjears 

 globular, while that of the male is oblong. In the crude lac of the shops these are 

 found mixed with the bodies of both sexes, often broken into jneces and with a pre- 

 dominance of the young ones. 



To this group also belong the wonderful forms of the genus Ceroplastes. These 

 are all tropical or sub-tropical forms, one species only of which overlaps into the west- 

 ern territory of the United States and occurs in Arizona ; Avhile two or more forms 

 occur in souihern Florida. Cuba and the larger West India islands afford a number 

 of species of this genus, some of which are very remarkable for their form and struc- 

 ture. Tlie female of one of these is shaped like a box tortoise, and has the outer in- 

 tegument divided into impressed spaces similar to a mosaic pavement. Its body is so 

 well concealed by this outer covering that it can only be detected by the closest 

 scrutiny. 



Ceroplastes rusci of Southern Europe has been described by various authors, and 

 more recently by Dr. Signoret in his classical "Essai," who takes it from Xiecaiiium, 

 to which it had been previously referred, and shows its aflinity to the present genus. 

 It has the form common to the species cited above, is of a grayish white color, with a 

 central convex disc, surrounded by a marginal row of eight variously shaped plates. 



