A very interesting fact has recently been developed in connection with the production of the sweet secretion known as honey-dew, on the leaves of plants. That leaves are often coated with this substance through the excretions of aphides is well known. A large number of observers write of honey-dew as wholly the product of these insects. Another portion contend that it certainly does occur frequently where these insects are not present; and hence we read that "honey-dew is often a secretion from the foliage of plants." No doubt this is the case sometimes. There are cases on record that would seem to admit of no other explanation. But it is now found that sweet secretions are emitted from scale insects in such great profusion as to cover pavements with the drip from them, in a single night. Professor Cook gives a detailed account of some of this work of the scale, and its connection with bee culture, in Science for January 23d. One case of honey-dew noticed on camellias, where certainly aphides were not present, is often referred to in scientific treatises, to show that it is a leaf secretion; but these plants are a favorite with species of coccus, and it is not at all impossible that, not suspecting the agency of these insects, they were overlooked when the aphides were found to be absent.

The fact now stated will lead to an opening of the whole honey-dew question again. - Independent.