278 THE WOODLANDS. 



faculty of observation than that of comparing similar 

 insects, one with another, and thus ascertaining 

 wherein they differ, and wherein they agree. It must 

 always be remembered that gall insects are particularly 

 subject to parasitism, and it is very probable that, 

 mixed with the true gall-flies, other insects will be 

 found which from their different general appearance 

 will at once be recognized as intruders. 



ARTICHOKE GALLS, so called because they bear a 

 miniature resemblance to the scaly calyx of the arti- 

 choke, are transformed buds, which are stunted and 

 rendered abortive by the puncture of an insect, and 

 thus converted into a kind of scaly gall. These galls 

 are consequently produced upon the young twigs, and 

 remain persistent upon the trees even till the winter. 

 If they are cut through the centre, the grub will be 

 found inclosed within the cell. So common are they 

 that it is almost certain that many specimens may be 

 collected in any oak wood, on the young undergrowth 

 where the oak is coppiced. 



Another kind of gall has been found on the young 

 twigs of oak, which are presumably caused by an 

 earlier puncture of the buds than the preceding, and 

 by a different insect. In this instance the exterior of 

 the gall does not become scaly, but they retain the 

 appearance of swollen buds, and might be mistaken 

 for such, only that their growth proceeds no further, 

 so that they never attain one-fourth of the diameter of 

 the artichoke galls. These are not so readily dis- 

 tinguished as the above, from their smaller size and 

 their resemblance to buds, neither are they so common. 

 They are, of course, produced by a different insect, as 



