The frequent association of inherited mental and nervous weakness with a high arched palate is now a well-established clinical fact. Thus Savage states that in “Genetous Idiocy” (_i. e._ idiocy which starts in fœtal life, and cannot be traced to any specific disease) the palate is usually keel-shaped, the molar teeth being closely approximated; they are also late in appearing and deficient in number. “Although this kind of palate may be present in healthy individuals or in those suffering from ordinary insanity, if it be associated with weak-mindedness or moral peculiarities in youth I believe one is justified in saying that the tendency to moral or intellectual deficiency is congenital.”[38] Only recently Dr. F. Warner has reported[39] to the Psychological Section of the British Medical Association the results of an investigation as to the occurrence of deformities amongst school children, and their relationship to defective vital and mental conditions. Out of 5344 children examined, physical deformity was noted in 399 cases, and of these 274 were boys and 125 girls, _i. e._ in the proportion 9·8 per cent. and 5 per cent. respectively. It was found that of these 25 per cent. exhibited evidences of low nutrition, 36 per cent. evidences of nervous weakness, and 31 per cent. of mental dulness. 117 cases were noted of deformity of the palate, 77 boys and 40 girls; and of these 35 per cent. gave signs of low nutrition, 39 per cent. of nerve weakness, and 35 per cent. of mental dulness. These defects were more marked and more frequent in the pauper than in the elementary public schools, in the proportion of 4·2 to 2·2. As to the character of the malformations, the following are the numerical statistics: In 105 cases, the palate was arched, narrow, high or vaulted; in 8, it was 𝖵-shaped; in 4 it was of the flat type. Dr. Langdon Down[40] had previously noticed and pointed out this frequent relationship, remarking that as the result of a large number of careful measurements of the mouths of the congenitally feeble-minded and of intelligent persons of the same age, he found with few exceptions a marked diminution in the transverse measurement between the posterior bicuspids, resulting in an inordinate vaulting of the palate. There was often noticed an actual deficiency in the bony structures of the posterior part of the hard palate, causing the velum to hang down abnormally, interfering with phonation.