The larynx in infancy presents certain conditions of acute or chronic nature which differ sufficiently from those encountered in later life to be of great interest and importance. The perfection of the technic of direct laryngoscopic examination has naturally removed the uncertainty which previously obscured the diagnosis and management of these disorders. It is the more surprising therefore to note the frequency with which this important procedure is still deferred or altogether omitted. It should be considered axiomatic that any stridor observed in infancy requires careful direct laryngoscopic examination regardless of other clinical findings which may apparently explain the disturbance. This contention is repeatedly emphasized in the study of 20 cases of chronic stridor in infancy on which this thesis is based.
EMBRYOLOGIC CONSIDERATIONS
A brief résumé of the more important phases of the development of the larynx is indispensable to an understanding of certain abnormalities encountered in infancy. It