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with difficulty that a pocket knife can cut them, while in contrast 
to these others can be easily compressed within the hand. One 
kind, which grows at the end of an oak bough on the catkins and 
young leaves, resembles bunches of red currants,—a tempting 
morsel on a hot May day,—while another kind away up amongst 
the top branches of a birch tree resembles a rook’s nest. One 
kind assumes the form of a hop-strobile or a miniature artichoke, 
and is named accordingly. Two others resemble fruit, one 
taking the shape and appearance of an apple, the other exactly 
like a cherry minus the strig; another is like a small pea covered 
with downy hairs, while another kind reminds us of a number of 
percussion caps neatly arranged on the bark of a small oak 
bough. Further examples might be given, but these kinds arrest 
our attention most speedily. 
Two of the most beautiful as regards wealth of colouring are 
the cherry gall on the oak, and the bedeguar gall on the wild 
rose, both of which, where touched by the sun’s rays, turn a 
bright red. 
The purdominant colour, however, is green, very delicate 
shades of which may be seen at various stages in the growth of 
the gulls ; in fact, as may be supposed from the positions they 
occupy, they are all more or less green in colour, changing only 
as they approach or attain maturity. The common oak marble 
may be used as an instance. When growing in June it is a 
golden yellow if it be in the shade, but green if more exposed to 
the action of light. By September, however, it has changed to 
brown, becoming darker as winter draws near. 
This is equally applicable to another species, 7.e, green at 
first, brown at last. 
One of the most noticeable, and certainly the prettiest of 
the galls on the sallow trees, is the 
Rosette Gall. 
This gall is caused by the larve of a small two-winged fly 
called Cecidomyia rosaria. ‘Vhe fly, according to Theobald, is 
rather pretty, the general appearance being dusky black with 
silvery hairs, the wings grey and iridescent, and the antennz as 
long as the body. The cluster of withered leaves at the end of 
the boughs of the willow tree bear a very close resemblance to a 
rosette, and hence its name It is a very pretty form of gall, the 
appearance being most uncommon. No doubt it is frequently 
reyarded as a mere cluster of withered leaves. Each larva 
inhabits a separate gall, and they undergo all the changes within 
the rosette. It is an example of the monothalamous group. 
They may be seen at best during the months of March or 
April, depending upon the climatic conditions of the spring in 
