142 INTERNAL ANATOMY OF INSECTS. 
fine down of a swan*. Probably the white powder or 
threads that appear to transpire through the skin of 
many other insects is of a waxy nature. In the larva of 
a beetle described by Reaumur, the flocoons are so ar- 
ranged as to give the animal some resemblance to a 
hedgehog, and when rubbed off they are reproduced in 
twelve hours b . Gyllenhal, speaking of Peltis limbata, 
observes, that when alive it is covered with a white pow- 
der resembling mould, which if rubbed off returns again 
as long as the animal lives c . 
It will not be improper to include under this head 
what further account I have to give of Lac, which though 
regarded as a resin, since Cocci sometimes certainly pro- 
duce wax d , probably has some analogy with the latter 
substance. When the females of this Coccus (C. Lacca) 
have fixed themselves to a part of the branch of the 
trees on wnich they feed [Fiats religiosa and indica, 
Butea frondosa, and Rhamnus Jujuba e ), a pellucid and 
glutinous substance begins to exude from the margins 
of the body, and in the end covers the whole insect with 
a cell of this substance, which when hardened by expo- 
sure to the air becomes lac. So numerous are these in- 
sects, and so closely crowded together, that they often 
entirely cover a branch ; and the groups take different 
shapes, as squares, hexagons, &c, according to the 
space left round the insect which first began to form its 
cell. Under these cells the females deposit their eggs, 
which after a certain period are hatched, and the young 
ones eat their way out. Though indisputably an animal 
a Reaum. iii. 318—. t. xxvi./. 1 — 6. 
b Ibid. 39G— . t. xxxi./. 20-29. c Insect. Suec. i. 257. 
J Vol. I. p. 327. c JV. Diet. d'Hist. Nat. xvii. 189. 
