DIRECT BENEFITS DERIVED FROM INSECTS. 325 



Reaumur tells us, that in the Levant, Persia, and China, 

 they use the galls of a particular species of Aphis for 

 dyeing silk crimson, which he thinks might lead us to 

 try experiments with those of our own country ^. That 

 dyes might be thus obtained seems probable from an 

 observation ofLinne's, in his Lapland Tour, upon the 

 galls produced by Aphis Pini on the extremities of the 

 leaves of the spruce-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 Terminalia citrina, a tree common 

 in India, yields a species of galls, the product of an in- 

 sect, which are 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 them "". A species 

 of mite {Tromhidiumtinctorium — Acarus, L.), a native 

 of Guinea and Surinam, is also employed as a dye ; and 

 it would be worth while to try whether our T. holose- 

 riceum, so remarkable 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, per- 

 haps, 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 



* Reaum. Hi. Preface, xxxi. " IccA. Lapp, i. 258. 



* Trans, of the Soc, of Arts, xx'nu ii]^ 



