Cases in which this occurs are known in popular language as child-crowing, or _spasmodic croup_, from the peculiar catch or crow which accompanies the entrance of air through the spasmodically contracted opening of the windpipe; a spasm which if severe and sufficiently continued closes the opening altogether, so that after fruitless efforts to get its breath the child dies suffocated. This affection occurs chiefly during teething, just as the fits of a hysterical girl oftenest occur during the transition from girlhood to womanhood; but many other causes besides the local irritation of the teeth may produce it, such as constipation, indigestible food, or disorder of the bowels. It does not often occur in perfectly healthy children; but an infant who is attacked by it is usually observed to have been drooping for some time previously, to have lost its appetite, to have become fretful by day and restless at night, and to present many of those ill-defined ailments which are popularly ascribed to teething. At length, after these symptoms have lasted for a few days or weeks, a slight crowing sound is occasionally heard with the child's respiration, shorter, more high-pitched, but less loud than the hoop of hooping cough. Usually it is first noticed on the child awaking out of sleep, but sometimes it is perceived during a fit of crying, or comes on while the infant is sucking. The spasm may have been excited by some temporary cause, and the sound which is its token may not be heard again; but generally it returns after the lapse of a few hours, or of a day or two, and its loudness usually increases in proportion as its return becomes more frequent. It will soon be found that certain conditions favour its occurrence; that the child wakes suddenly with an attack of it, that excitement induces it, or the act of swallowing, or the effort at sucking, so that the child will drop the nipple, make a peculiar croupy sound with its breathing, and then return to the breast again. Throughout the whole course of the affection, its attacks will be found to be more frequent by night than by day; and to occur mostly soon after the child has lain down to sleep, or towards midnight, when the first sound sleep is drawing to a close.