Let us change the picture. Z is a bright-eyed, dark-skinned girl of 9 years. She is dark-skinned because her father is a mixture of Indian and Spanish. The mother is of Irish descent. With her strangely mated parents and two brothers she lives in a dirty, cramped, and poorly furnished house in the country. The parents are illiterate, and the brothers are retarded and dull, though not feeble-minded. It is Z's turn to be tested. I inquire the name. It is familiar, for I have already tested the two stupid brothers. I also know her ignorant parents and the miserable cabin in which she lives. The examination begins with the 8-year tests. The responses are quick and accurate. We proceed to the 9-year group. There is no failure, and there is but one minor error. Successes and failures alternate for a while until the latter prevail. Z has tested at 11 years. In spite of her wretched home, she is mentally advanced nearly 25 per cent. By the vocabulary test she is credited with a knowledge of nearly 6000 words, or nearly four times as many as X, the boy of cultured home and scholarly parents, had learned by the age of 8 years. Five years have passed. When given the test, Z was in the fourth grade and, as we have already stated, 9 years of age. As a result of the test she was transferred to the fifth grade. Later she skipped again and at the age of 14 is a successful student in the second year of high school. To assay her intelligence and determine its quality was a task of forty-five minutes. The above cases, each of which could be paralleled by many others which we have found, will serve to illustrate the fact that exceptionally superior endowment is discoverable by the tests, however unfavorable the home from which it comes, and that inferior endowment cannot be normalized by all the advantages of the most cultured home. Quoting again from Stern, "The tests actually reach and discover the general developmental conditions of intelligence, and not mere fragments of knowledge and attainments acquired by chance." PART II GUIDE FOR THE USE OF THE STANFORD REVISION AND EXTENSION CHAPTER VIII GENERAL INSTRUCTIONS