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A disease of infants, characterized by suspension of respiration at intervals; great difficulty of breathing, especially on waking, swallowing, or crying; ending often in a fit of suffocation, with convulsions. The pathology of the disease has been supposed to consist in an enlargement of the thymus gland, or of the glands of the neck pressing on the pneumo-gastric nerves[?]. The ear, by auscultation, at a distance from the chest, detects an incomplete, acute, hissing inspiration, or rather cry; whilst the expiration and voice are croupal, both at the accession and termination of the paroxysm. The heart's action has been observed to be distinct and feeble. These symptoms are often accompanied by rigidity of the fingers and toes; the thumb being frequently drawn forcibly into the palm of the clenched hand, whence the name Carpo-pedal spasm, applied, at times, to the disease.