GALL MITES, 333 



CASE number of small tacks had been driven throupjli the leaf from 



Xv'i. 



the under side, whence it was named either by him or others 

 the lime-leaf nail-gall. Now this nail-gall, when cut open and 

 examined, usually appears empty of any living inhabitants, not 

 empty in itself, but filled with a mass of fine vegetable hairs of the 

 nature of those that cover the under side of the leaf, but longer, 

 and exaggerated in size and number. Reaumur, like many others, 

 for long examined hundreds of these galls without finding any in- 

 sect in them ; but he records that at last he found that his failure 

 was due to his searching for them too late; and that, when he sub- 

 sequently examined them at an earlier stage while they were still 

 green, he found insects in almost every gall examined. He adds^ 

 that he never saw more than one in each ; although there was an 

 appearance as if they might be in company ; and he describes thems 

 as long j under a strong glass not appearing thicker than the stalk 

 of a small pin. They were yellowish, like the interior of the gall. 

 "WTiat makes them more difficult to find, says he, is that they do 

 not like to walk. " I often saw one, but was uncertain whether 

 it was a grub or not, until it pleased to put itself in motion. It is> 

 towards the base of the gall that we find them : when the galls g<tt 

 old, some opening or crack takes place, by which mites and 

 strange insects introduce themselves. I have seen, for example^ 

 mites ensconced there." It is now ascertained that mites are not 

 only ensconced there, but are the makers of the gall ; and 

 Reaumur's observations had been quoted to show that it was 

 them that he discovered. We cannot agree with this : the closing 

 words of his remarks which we have quoted seem to show that he 

 was perfectly alive to the distinction between a mite and a small 

 grub ; and although Reaumur might be, and probably was correct 

 in assigning the early time of these galls as the date when their 

 makers were to be found inside, yet, we believe the grubs that he 

 saw were not themselves Phytopti, but possibly some carnivorous 

 larvae that had come in to feed upon them. We suspect he never 

 saw the Phytopti themselves, for he only found one grub in each 



