274 DIRECT BENEFITS DERIVED FROM INSECTS. 



tremities of the leaves of the spmce-fir, which, he informs us, 

 when arrived at maturity, burst asunder, and discharge an 

 orange-coloured powder which stains the clothes ^ ; and Mr. 

 Sheppard confirms this observation, the galls of this Aphis 

 abounding upon fir trees in his garden. In fact, we are told 

 that Termlnalia citrina, a tree common in India, yields a 

 species of gall, the product of an insect, which is sold in every 

 market, being one of the most useful dyeing drugs known to 

 the natives, who dye their best and most durable yellow with 

 it.^ A species of mite ( Trombidium tinctorium), a native of 

 Guinea and Surinam, is also employed as a dye ; and it would 

 be worth while to try whether our T. holosericeum, so remark- 

 able for the dazzling brilliancy of its crimson and the beautiful 

 velvet texture of its down, which seems nearly related to 

 T. tinctorium, would not also afford a valuable tincture. It 

 is not likely, perhaps, that many better and cheaper dyes 

 than we now possess can be obtained from insects ; but 

 Reaumur has suggested that water-colours of beautiful tints, 

 not otherwise easily obtainable, might be procured from the 

 excrements of the larvae of the common clothes-moth, which 

 retain the colour of the wool they have eaten unimpaired in 

 its lustre, and mix very well with water. To get a fine red, 

 yellow, blue, green, or any other colour or shade of colour, 

 we should merely have to feed our larvae with cloth of that 

 tint.3 



Wax, so valuable for many minor purposes, and deemed 

 with us so indispensable to the comfort of the great, is of 

 still more importance in those parts of Europe and America 

 in which it forms a considerable branch of trade and manu- 

 facture, as an article of extensive use in the religious cere- 

 monies of the inhabitants. Humboldt informs us, that not 

 fewer than 25,000 arrobas, value upwards of 83,000/., were 

 'formerly annually exported from Cuba to New Spain, where 

 the quantity consumed in the festivals of the church is im- 

 mense, even in the smallest villages ; and that the total export 

 of the same island in 1803 was not less than 42,670 arrobas. 



1 Lack. Lapp. i. 258. 

 3 Reaum. iii. 95. 



2 Trans of the Soc. of Arts, xxiil. 411. 



