Obesity or lipomatosis is a nutritive expression of degeneracy especially noticeable in the second dentition, at puberty, and sometimes at the climacteric. As Féré has shown, lipomatosis (first noticed by Cruveilhier) is an expression of stress at the period of evolution. Youthful obesity occurs in descendants of degenerates. In my experience it is attended by great liability to disease and systemic weakness when under morbid influence. These lipomatosic children are liable to rheumatism (more properly gout) and great hemorrhage from slight causes. Youthful obesity is sometimes, as Féré remarks, associated with precocious maturity and resultant early senescence, but more often with extended infantilism, as in the case of Dickens's "fat boy." In connection with this question of obesity I examined 267 corpulent school children and adults. Nearly all had marked stigmata of degeneracy; 92 per cent. had deformed ears to a marked degree; 66 per cent. had arrested development as compared with their age, while 12 per cent. presented excessive development; 34 were too young to show the final form and size of the jaw. Of the 34, in about 33-1/3 per cent., the molars, incisors, cuspids and bicuspids were present; 96 per cent. of these had small teeth. Of the remaining 233, 87 per cent. had arrested development of the upper jaw, 22 per cent. of the lower jaw, 64 per cent. had V or saddle-shaped arches or their modifications and protruding teeth; 17 per cent. had hypertrophy of the alveolar process; 83 per cent. had small teeth; 27 per cent. had extra tubercles upon the molars; 82 per cent. had stenosis of the nasal cavity more or less marked; 36 per cent. had deflection of the nasal septum to the left, and 29 per cent. to the right; 21 per cent. wore glasses for eye defects. In 58 per cent. there was enlargement of the thyroid gland, and in 7 per cent. arrest of development of the same. [Illustration: FIG. 108.] [Illustration: FIG. 109.] [Illustration: FIG. 110.]