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annual report op new-york 
as a grove of maples could be seen. And what appeared to be 
most singular, whilst the maples growing in forests were every¬ 
where affected in this manner, those standing alone as shade 
trees in fields, and those planted around houses and along the 
streets of villages remained green and wholly exempt from the 
prevalent malady. 
The cause of this fading of the leaves was readily discovered 
upon examination. They were found, when inspected, to present 
the appearances which are very well illustrated, plate 4, figure 6. 
The green parenchyma or pulpy substance of the leaf was de¬ 
stroyed in spots and irregular patches, leaving only the fine net¬ 
work of veins and the transparent cuticle. These spots were 
commonly in rings or in segments of a circle, with the centres 
green and unaffected. In addition to these, holes of a nearly 
circular form appeared in the leaves, about a quarter of an inch 
in diameter, with others of a smaller size. A dozen or more of 
these holes were at that time found in almost every leaf. And 
some of the pieces which had been cut out of the leaf, forming 
these holes, might be observed, adhering like round scales to the 
surface of the leaf, some on its upper others on its under side. 
On elevating this scale from the surface of the leaf, another 
smaller one was found beneath it, and between them was a small 
white worm, which was evidently the artizan by whom all this 
work had been done—cutting out these circular pieces from the 
leaf to form a cloak for himself, and when hungry feeding upon 
the pulpy substance of the leaf, thus forming the circular and 
irregular spots seen upon it. Occasionally one of these scales 
might be observed to move slightly along, the worm at such 
times protruding its head from under the edge of the scale and 
with its feet pulling its unwieldy domicil to another part of the 
leaf. 
Generally the worm was found inclosed by three of these 
round pieces which it had cut from the leaf probably at succes¬ 
sive periods of its life. First was a small one upon its back, 
about 0.18 long and two-thirds as broad, slightly concave on its 
under, convex on its upper side. Next was a larger piece, of 
similar form, placed on the under side of the worm, its edges 
overlapping those of the first piece, its concavity facing the con- 
