THE ENTOMOLOGIST. 187 



scarlet field-poppy; C. Crataegi lives in those leaf-tufts which 

 may be said to decorate the tips of the shoots of the white- 

 thorn, and these were so common last year that I could not 

 find in my garden a single tip that had escaped this familiar 

 ornamentation ; C. Veronicas feeds within the running stems 

 of the germander speedwell, fastening the leaves together, 

 and forming a densely hairy pouch, in the centre of which 

 the creature undergoes its transformation ; C. bursaria forms 

 pyramidal hairy galls on the upper side of the leaves of the 

 ground ivy ; C. Urticse lives in galls on the leaves and stems 

 of the stinging nettle; C. Pyri in the rolled-up leaves of 

 young pears ; C. Linariae makes those pretty little tufts on 

 the tips of the buds of the yellow toad-flax ; and so I might 

 go on with a hundred other species, each of which confines 

 its attention to one particular tree, shrub or herb, to decorate 

 in its own fanciful way. It is one of this ubiquitous genus 

 of insects that your correspondent has observed in the 

 wheat, and one which, although perhaps seldom noticed by 

 agriculturists, is familiar to men of science, to whom it was 

 made known by the father of Entomology in this country, 

 the late Rev. William Kirby, who published respecting it, in 

 the ' Linnean Transactions,' one of the most complete ento- 

 mological papers we possess. In the very same volume of 

 the ' Transactions ' is a paper by Mr. Marsham on the same 

 insect; and subsequently the late estimable Professor Henslow 

 published, in the ' Journal of the Royal Agricultural Society,' 

 some additional information ; and the communications of 

 these three eminent and most talented writers comprise all 

 we know of this minute enemy of the farmer. If there be a 

 fault in these learned papers, it is to be found in the inferences 

 they contain, not in the facts they record : their facts are 

 indisputable. I may acknowledge that inferences and 

 numerical calculations generally fail to convey to my mind 

 that satisfactory conviction which results from a simple state- 

 ment of facts. I mention this because our French and 

 German naturalists have followed us in this matter, and have 

 made their own calculations, which have induced unnecessary 

 alarm. I will cite Mr. Kirby's statistics and inferences 

 regarding this particular insect, the wheat midge. *' In order 

 to ascertain," says Mr. Kirby, " the quantity of mischief 

 produced by one Tipula (Cecidomyia) within particular 



