5090 THE ZooLoGist—SEPTEMBER, 1876. 
the village of La Grave, at the base of the ‘ Aiguille du Midi’), remarkable 
for the extent to which nearly all were infested by the red parasite described 
by De Geer as Acarus libellulie (perhaps a species of Trombidium). Of the 
thirteen examples captured casually only one was free from parasites, the 
number of them on the others being respectively 7, 8, 9, 15, 17, 19, 28, 
47, 51, 73, 96 and 111, or a total of 481 on twelve individuals. They were 
firmly fixed on the nervures towards and at the base of the wing, almost 
invariably on the under side; but whatever might be the number on any 
particular dragonfly it was always divided nearly symmetrically on the two 
sides of the insect—those much infested having a very pretty appearance, 
from the wings looking as if spotted with blood-red. He had no doubt that 
the Acari must have attained their position by climbing up the legs of the 
dragonfly when at rest; probably they did not quit it till the dragonfly died, 
or perhaps they died with it, so firmly were they fixed. He remarked that 
the history of the Acari was involved in much obscurity, for it appeared by 
no means certain that all those existing could ever gain access to dragon- 
flies; just as in the case of the bed-bug and the house-flea, where there 
must be myriads that never have an opportunity of tasting human blood. 
He further noticed that, at the meeting of this Society on the 1st of August, 
1864, he exhibited a dragonfly from Montpellier similarly attacked, and it 
was recorded as Diplax striolata (Tr. Ent. Soc., 2nd series, vol. ii., Proc. 
xxxvi). This was an error, the insect being D. meridionalis, which seemed 
to be particularly subject to attack. 
Mr. F. Smith read the following :— 
Note on Nematus gallicola, Steph. 
“‘ This is one of the commonest species of sawfly found in Europe; it is 
the maker of the well-known red galls so plentiful on leaves of different 
species of willow. The galls are, as Mr. Cameron observes, in his com- 
munication to the ‘Scottish Naturalist,’ somewhat local, but they are 
extremely abundant in many situations. I have on many occasions collected 
large quantities of leaves, more or less covered with galls, and have bred 
mavy hundreds of the flies—all proving on examination to be females. 
Mr. Cameron observes, in the paper alluded to, ‘The male is quite 
unknown to me, and this appears to have been also the case with Hartig.’ 
Last spring I collected, in the London district, a quantity of the galls, 
placing them in a large flower-pot half-filled with garden mould. The larve 
soon quitted the galls and buried themselves in the mould for the purpose 
of undergoing their transformations. About a mouth after this the flies 
began to issue forth, probably to the number of from five to six hundred: 
among this number I had the satisfaction of finding two males. This sex 
closely resembles the female, but has a narrower body, longer antenne, and 
the tip of the abdomen is pale; the abdomen is also narrower, and not, as 
ee a a 
