346 0)1 Medical Entomologif, 



a small head, and long thin antennae of thirteen or fifteen 

 articulations. The wings large, and almost without ribs. 

 The thorax, as it were gn:>bous. The abdomen compressed 

 on the sides and sharp below, where it contains, between 

 two scaly laminre, a sting bent in a spiral form, and which 

 issues only when the insect wishes to deposit its eggs under 

 the epidermis of a plant. Its prick occasions a protube- 

 rance called gall, which always increases, and in which the 

 larva lives till the time of its metamorphosis*. It then 

 gnaws through its prison, and the place where it issues is 

 marked by a hole with which the gall is pierced : some- 

 times, however, the larva dies before that period, or is not 

 able to form for itself a passage ; in that case the gall re- 

 mains without being perforated. 



Cynips Ouercus — Gall Fly. — The oak affords nourish- 

 ment to several kinds of cynips, which all prick it in cer- 

 tain parts ; such as the branches, flowers, leaves, and foot- 

 stalks. The species which attack the latter part have a 

 black body, whitish legs, and brown thighs. It produces 

 the lar2:e round gall full of tubercles, a decoction of which, 

 mixed with a solution of the sulphate of iron, composes ink, 

 and almost all black colours. 



The gall (called commonly the gall-nut) was formerly 

 considered as an excellent remedy ; and I consider as very 

 blameable the forgetfulness to which it appears to be at 

 present condemned. It has a great analogy indeed to cin- 

 chona ; and if it cannot, in certain circumstances, supply 

 its place, there are others in which it is superior. Hippo- 

 crates employed it externally against affections of the ma- 

 trix, and Galen cured intermittent fevers by administering 

 it in doses of a gros. 



The external and internal use of gall-nuts is indicated in 

 asthenic diseases of the lymphatic and cellular systems, in 

 some mucous fluxes too abundant,' such as blennorrhea and 

 leucorrhca. It is a powerful auxiliary for keeping in con- 

 tio'uitv parts which have been divided. 



The gall nut of the oak, by simple infusion in water, 

 deposits crystals disposed in the form of a sun, of a gray 

 colour, anu an acid styptic taste. It is gallic acid, which 

 retains the properties of the substance that furnished it- 

 Boiling alcohol dissolves equal parts of that acid ; cold, it 

 dissolves a fourth. The gallic alcohol which results from 

 it ought, in my opinion, to surpass in virtue all the pre- 

 parations of gall nuts. hitherto employed. 



• Cuvier Tai. ELm. de I'Hiit. Nat. da Animaux. 



Cynips 



