Mr. John White, of Pittsfield, Mass., sends us specimens of an aphid, which seems, he says, to attach itself to a leaf, and to seem almost inseparable from it, doing much damage to the foliage. Prof. Riley decides it to be one of the aphid family, probably the one known as Siphomophora rosae. These are attacked by a parasite which destroys and puffs them up, making them seem much larger than when in their natural state - as house-flies are attacked by a fungus in the fall of the year, and are attached to glass by fine threads, as most observing persons have noted. Possibly in some way these aphides get attached to, and destroy the rose leaves, but we have no positive information at hand on this point.