This booklet consists chiefly of the pedigree data of nearly 300 pupils observed at the Clark School for the Deaf in Northampton, Mass., between 1930 and 1940. Included with these data are condensed histories and audiogram records of all relatives of the deaf pupils about whom information could be obtained. The volume is therefore chiefly made up of pedigree charts, with explanatory footnotes in cases of deafness which were thought to be congenital and hereditary.
The summary of this huge collection of data is, however, of extreme interest. We learn that the deaf children were no more susceptible to middle ear infections than their hearing brothers or sisters, a point which casts considerable doubt on the frequent assertions of parents that their child's deafness is due to middle ear disease. Deafness in children tended to occur at random through the family, indicating that order in family had no particular influence