List of the Insect Fauna of the Coimty. 101 



folk-lore of galls would yield a goodly chapter, but with 

 little help towards the present enquiry.'^ Compare the well- 

 known remarks of many classical writers, and some curious 

 information given in Kirby and Spence's ' Introduction to 

 Entomology.' 



Linne tells us the insect punctures the plant, and the out- 

 flow of sap from the wound is the cause of the formation of 

 the gall. " Cynipes succo plantarum e vulnere inflicto 

 stillante et in gallam in qua habitant larvae excrescente 

 victitant." [Gmelin's Linne, ' Syst. Nat.,' vol. i., pars, v., 

 p. 2650.] . De Geer, Eeaumur, Roesel, Frisch, Malpighi, and 

 others had previously promulgated this convenient but 

 thoroughly untenable theory ; still this was generally 

 accepted to the days of our own Kirby and Spence. 



These fathers of British Entomology epitomized the in- 

 formation on this puzzling subject thus :® — "How the mere 

 insertion of an Qgg into the substance of a leaf or twig, even 

 if accompanied, as some imagine, by a peculiar fluid, should 

 cause the growth of such singular protuberances around it, 

 philosophers are as little able to explain as why the insertion 

 of a particle of variolous matter into a child's arm should 

 cover it with pustules of small-pox. In both cases the effects 

 seem to proceed from some action of the foreign substance 

 upon the secreting vessels of the animal or vegetable ; but of 

 the nature of this action we know nothing. This much is 



ascertained by the observations of Reaumur and Malpighi 



that the production of the gall, which, however large, attains 

 its full size in a day or two, is caused by the Qgg or some 

 accompanying fluid, — not by the larva, which does not appear 

 until the gall is fully formed ; that the galls which spring 

 from leaves almost constantly take their origin from nerves ; 

 and that the egg, at the same time that it causes the growth 

 of the gall, itself derives nourishment from the substance 



7 Keferences to fossil galls and some antiquated information occur in 

 Mr. Albert Muller's memoir, ' In Memoriam Wilson Armistead, of Vii'- 

 ginia House, Leeds.' 'Zoologist,' 2nd ser., vol. iii., pp. 1196—1208; 

 May, 1868. 



8 ' An Introduction to Entomology.' By William Kirby and William 

 Spence. 4th ed. (1822), vol. i., p. 450 ; 5th ed. (1828), vol. i., p. 448. 



