Criticizes vocabulary tests as a measure of intelligence on grounds that they measure a special ability rather than intelligence. However high concurrent validities have been obtained between vocabulary tests and the Binet-Simon Scale on 631 school children indicating that children of a given mental age have approximately the same vocabulary regardless of their chronological age. Vocabulary growth was constant and regular. No sex differences for the median vocabulary at each mental age were found. Foreign language used at home resulted in inferior vocabulary of English for the initial few years of school but it eventually caught up by the mental age of 12 yrs. Reliability of vocabulary sampling indicated that school children had a high and uniform correlation as compared to university students. (PsycINFO Database Record (c) 2016 APA, all rights reserved)