3°8 
STRANGE DWELLINGS. 
table agency. That their substance was vegetable was a fact 
easily settled, but some botanists thought that they were merely 
a kind of fungus or lichen, while others supposed that they were 
the work of some parasitic insect. 
When closely examined, these ‘ spangles’ are seen to be discs, 
very nearly but not quite flat, fastened to the leaf by a very 
small and short central footstalk. Reaumur set at rest the 
question of their origin by discovering beneath each of them 
the larva of some minute insect, but he could not ascertain the j! 
insect into which the larva would in process of time be deve- 
loped. The task of rearing the perfect insect from the gall is 
exceedingly difficult, the minuteness of the species and the 
peculiar manner in which the development takes place, being 
two obstacles which require a vast expenditure of care and 
patience before they can be overcome. 
Supposing a branch containing a number of infested leaves 
to be placed in water and surrounded with gauze, it will die in 
a week or two, and yet there will be no sign of an insect. If 
the branch be kept until the winter has fully set in, the desired 
insects will still be absent, and the experimenter will probably 
think that his trouble has been thrown away. The real fact is, 
that the little insects are not developed until the spring of the 
following year, and that they pass through their stages of the 
pupal and perfect forms after the leaves have fallen, and while 
they are still lying on the ground. 
Mr. F. Smith, who has given so much time and research to 
the history of the hymenoptera, has discovered the insect that 
inhabited the galls to be Cynips longipennis , and has remarked 
that the perfect insects do not make their appearance until the 
month of March. I have had many specimens of this tiny and 
beautiful insect. I 
