A new experience in diagnosis is exhilarating even though the newness may be original only because of ignorance of the observations of others. This may be such an example but, so far as I know, a similar case has not been recorded.
I had been baffled by two prominent white ridges (see photograph) on the dorsum of the tongue of a 2½-year-old boy. These ridges were located laterally and extended symmetrically in a slight arc from the anterior border of the tongue directly posteriorly for about ½ in. These had been first noticed, quite by chance, by the boy's mother three weeks prior to his being referred to me by the family physician. The lesions were apparently symptomless to the child but gave his apprehensive mother a great deal of concern.
Upon scraping with a curette, I found the ridges firmly coherent to the tongue, and it was only