184 Mr. J. O. Westwood on the Parasites of the Larva 
XXXVII. Notice of a minute Parasite inhabiting the 
Larva of the Stylopidce ; and upon the Animal produced 
from the Eggs of Meloe . By J. O. Westwood, F.L.S. 
[Read June 6, 1836.] 
The more we learn of the Strepsiptera, the more extraordinary 
does this little tribe of insects appear ; and the more does it 
require investigation, especially as regards the economy of its 
various species. With the hope to clear up some of the diffi- 
culties connected with these insects, I endeavoured, in the course 
of the past spring, to obtain information by capturing many spe- 
cimens of Andrenidce, and I succeeded in finding nearly a dozen 
specimens of Andrence Gwynnana and parvula Hying about, 
infested with specimens of the larvae of Stylops, of which the 
heads were exserted between the abdominal segments as usual. 
My exertions were however defeated by a very minute creature, 
which is parasitic upon the Stylops. During the pleasant trip, 
made last autumn from Bonn to Cologne, by the naturalists 
assembled at the former city, the Senator Van Heyden, who has 
paid great attention to this order of insects, informed me that he 
had observed a very minute Acarus issue from an apparently 
dead larva of a Xenos, and which was quite unlike any other of 
the Acaridce , of which he has also made a very extensive investi- 
gation. Subsequently, Mr. Pickering, who it will be remembered 
exhibited some stylopized bees at the April meeting of the 
Society, informed me shortly afterwards that his larvae had pro- 
duced a number of minute Acari, which he gave me for examina- 
tion, and which he had placed in spirits of wine, in which they 
were so minute as to be scarcely visible even with a common 
1| inch-focussed lens. 
My own bees, however, afforded me but too many oppor- 
tunities of examining this curious little animal in a living state ; 
for I observed that the bees (which I kept in wide-mouthed 
bottles, feeding them with flowers and moistened lump-sugar, 
upon which they thrived well and were very active), from time to 
time, bent their abdomens downwards, applying them against the 
leaves of the flowers ; and on examining the cause of this motion, 
I perceived that it was for the purpose of dislodging a number of 
minute creatures, similar to those which Mr. Pickering had given 
me, and which were creeping about amongst the hairs at the 
extremity of the abdomen ; and which, with a strong lens, I saw 
