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of the Beech-leaf; swellings more or less spindle-shaped on the 
twigs, pedicils or peduncles; hard button-like excrescences on 
the same parts; bladder like vesicles on the ribs of leaves, as 
commonly on the ash; and rolled edges of leaves as in Acer 
campestre; all these are quite closed, and the larve present 
the same puzzle as did the apples in the dumpling to King 
George III. We have again purse-like forms, where parts of 
the plant have been drawn together, but left open at the ends; 
leaf buds and flower heads similarly drawn together; scales 
between two modified leaves; or tufts of leaves as in some of 
the Conifere. 
I found in May last, near Coniston Lake, a large Yew, 
whose every tuft of new leaves was aborted by a Cecidomyid larva, 
giving the whole tree so very remarkable and unusual an 
appearance, that I at first took it for some unknown variety. 
Further, rolled leaf edges may form open trumpet-shaped cones, 
each with its larval inhabitant; and felted masses of epidermal 
hairs, constitute what serves as a mere shelter or covering. 
These are but a few of the more common and striking methods 
in which the Gall-Midge larve abort their host plants, pro- 
ducing conspicuous gall-growths. 
Dr Loew to whom all students of Diptera, as well of this 
family as of so many others, are deeply indebted, says: “‘at one 
extremity is a true gall, a vegetable growth of definite form, 
attached to a plant by a small portion of its surface, not 
otherwise deforming that part of the plant; at the other, a 
simple deformation, folding of a rib, arrest of a bud, stalk, twig, 
or seed-vessel.” 
It would appear impossible to draw any hard and fast line 
of demarcation between these varied plant structures, and at 
present it seems a mere waste of time to attempt a classification 
on the basis of gall architecture alone, as has been done by 
Bremi. 
Although the habit of gall-making characterizes the 
majority of the family, yet it may here be pointed out that many 
very notable exceptions occur, and that too with species that 
are among the most numerous and most widely distributed of 
