like the structure of the anterior lobe of the pituitary, while the central part contains more nervous elements. Although originally it may have been a sense organ, it is now purely glandular in its activities.

Function. This gland seems to be associated with other glands that are essential to the growth and development of the child to puberty. It has its greatest activity during the first few years of the infant's life, and then gradually ceases its activity toward puberty, although it probably normally never entirely degenerates. It apparently has control over sexual and mental development, and especially seems to inhibit too rapid sexual development in young children. If the pineal gland is removed from young animals, they more rapidly develop sexually and have an early puberty.

This gland does not seem to be necessary to life, but McCord and others have found that its removal apparently increases mental and sexual development when the operation is performed early in the animal's life. Horrax also found that the testicles of guinea-pigs better and more rapidly developed, and the females bred earlier after pinealectomy. The symptoms from its removal in the adult animal are unimportant.

Enlargements or growths of this small gland rapidly cause pressure symptoms and circulatory disturbances, as the gland is in direct contact with the large veins in the center of the brain; also pressure in this region may cause hydrocephalus. In the adult, tumor growths of the pineal gland can apparently cause only headache and the symptoms of a cerebral tumor in this location. Uncomplicated enlargement of the pineal gland is rare.

Extracts of the pineal gland when injected intravenously cause a lowered blood-pressure, perhaps some heart disturbance, and possibly a glycosuria. A lowered blood-pressure is caused by injections of any extract of nervous tissue. Therefore there are no characteristic symptoms from such injections.

If there is tumor growth or other disturbance causing an insufficiency of this gland in early childhood, there is an increased rapidity of sexual development; the external genitals

are increased in size and hair grows on the pubis. The child also rapidly develops mentally and physically, and becomes precocious.

Extracts from the pineal body are best prepared from young bullocks, as adult pineal glands have not been found to have the activity that the glands of young animals possess.

It was at first thought that feeding this gland to young children of slow development would increase their growth and their mental activity, and would cause an early maturity of the sexual glands. This theory was in direct opposition to the belief that privation of the secretion of this gland caused just this condition, This paradox has lately been found not to be true. In other words, it is not proved that feeding this glandular tissue to defective children causes any improvement in their condition, although McCord found that feeding pineal extracts from young animals to young animals stimulated the growth of the latter to normal (not to giant size) and stimulated their mental and sexual development.

A number of cases are on record, some of which have been proved to have a pineal tumor and others which are supposed to have insufficient secretion from this gland, which have shown very early development of all the secondary sex characteristics. This gland, supposed at some ancient time to be a sense organ for sight, is said by McCord' to "contain an active principle capable of inducing pigment changes independent of and wholly apart from environmental conditions."

When this gland degenerates it seems to deposit so-called "brain sand," and roentgenograms of adult skulls may show shadows from the calcification of this gland.

Children who mature early and at the same time develop an abnormal amount of fat, may have a hyposecretion of the posterior pituitary or a disturbance of the pineal gland. It is frequently impossible in abnormal children to decide how many and which endocrine glands are dysfunctioning.

At the present time it would seem that the thymus and the pineal glands have considerable to do with the normal development of the child, especially its sexual development. Disturb1 Journ. of Exp. Zoology, May, 1917, p. 207.

ance of the thyroid, the adrenals, and of the pituitary can cause the child's development to be abnormal. After puberty it would seem that the pituitary, thyroid, adrenals, ovaries and corpus luteum in the female, and the testicles and perhaps the prostate in the male, govern normal health and sexual life. Even if it is denied that the thymus and the pineal glands have internal secretions, still it cannot be denied that they have some important function during early childhood.

Besides the early precociousness in sexual development thought to be due to hyposecretion of the pineal gland, it has been suggested that a hypersecretion or an increased secretion of this gland during the age of normal puberty would postpone maturity and continue and perhaps perpetuate for a time infantile sexual organs. Infantilism, the lack of mental and body growth, may be due to many causes, and is characterized by many types, but in most cases there is a slow development, or lack of development, of the secondary sexual characteristics. In the female normal pelvic and mammary gland growth does not occur, pubic hair is absent, and the menstrual function is in abeyance. In the male, the genitals remain small, hair does not grow on the face or pubis, and the voice remains that of a child.

Herter, in 1908, thought there was a type of infantilism due to intestinal disturbance. It is quite probable that some of these conditions are due to privation of some type of vitamines necessary for complete health and growth of the body and for the production of the hormones of one or more endocrine glands. It is possible that disturbance or absence of the secretion of the pineal may be one of the many causes of cachexia in young children. Timme1 suggests that pineal gland disturbance may be a cause of progressive muscular dystrophy.

As yet pineal gland treatment of children who are defective mentally and who do not grow or develop is purely experimental. However, to children who are delinquent, and do not show distinct indications of other glandular insufficiency, small doses of pineal extract may be given. Tablets of pineal extract may be obtained for such administration which represent 120 of a ' Archives of Internal Medicine, Jan., 1917, p. 79.

grain. Theoretically such a dose need not be given more than once or twice a day.

PANCREAS

Function. The pancreas is a gland furnishing two secretions, one, the pancreatic juice, which passes by ducts into the duodenum, digests both proteins and starches; the other secretion, furnished by the islands of Langerhans, reaches the blood by absorption, and it is this secretion that is closely associated with the glycogenic function. When the pancreas is extirpated, or there is disease of these islands of Langerhans, the sugar of the blood is increased and glucose appears in the urine. While many organs of the body are associated in the glycogenic function, namely, the pancreas, liver, muscles, suprarenals, and the posterior pituitary, disturbances of other glands may so upset the glycogenic metabolism as to cause glycosuria; but if the islands of Langerhans are diseased, diabetes mellitus occurs. Focal infection is probably a frequent cause of disease of this part of the pancreas, and therefore of glycosuria and, later, of diabetes mellitus.

If the pancreas is removed, the animal dies. If the liver is in trouble, the pancreas may hypertrophy and attempt to do extra work, especially the islands of Langerhans. On the other hand, if the pancreas is in trouble, the liver seems to produce more sugar, the sugar of the blood is increased, and glycosuria occurs. In other words, the internal secretion of the islands of Langerhans, or the hormones from this glandular tissue, seems to control the production of sugar by the liver, and perhaps the ability of the muscles and tissues to use sugar. The reverse seems to be true of the adrenal secretion. If there is too much adrenal hormone in the blood, it seems to stimulate the production of sugar, perhaps by activating the posterior lobe of the pituitary. The hormones furnished by the islands of Langerhans seem to cause normal oxidation of the glycogen in the muscles.

As stated, entire removal of the pancreas causes diabetes and is rapidly fatal, and partial removal of the pancreas will cause a mild diabetes. In mild forms of diabetes in the human being removal of carbohydrates from the food prevents glycosuria,

while in severe types privation of carbohydrates does not prevent glycosuria, glucose being formed from proteins. Investigations have seemed to show that in from 34 to % of the cases of diabetes mellitus lesions of the islands of Langerhans have been found. This does not show that the disturbance is always primarily in the pancreas.

While excessive eating of carbohydrates may be a predisposing cause of diabetes, excessive eating of proteins may also be a cause, i.e., if the pancreas is overworked and irritated, disturbance of the islands of Langerhans may occur. Also the internal secretion of the pancreas seems to be closely related nervously, or by secretion, to the brain, and any disturbance that causes a hypersecretion of the posterior pituitary and infundibulum will cause glycosuria. Cerebral injuries and disturbances may cause glycosuria, probably because the posterior lobe of the hypophysis is stimulated. Suprarenal disturbances cause glycosuria, perhaps by the effect on the pancreas.

It has been shown that the blood from the pancreatic vein of a healthy animal will not prevent or stop the glycosuria of experimental diabetes. Therefore it is not the secretion of the islands of Langerhans that is in the blood that prevents diabetes. Also, feeding of pancreatic substance and pancreatic extracts does not cure or seem to in any way affect the progress of diabetes.

It may be briefly mentioned that it is the liver that converts carbohydrates into glycogen, which it stores until it is needed for muscle use. When it is needed, it is reconverted into glucose, and is carried to the muscles and tissues, and what is not used for immediate energy is stored in the muscles as glycogen again.

Inflammations of the pancreas may occur without causing glycosuria, provided that the islands of Langerhans are more or less intact. There are various tests to determine the efficiency of the pancreas as evidenced by glucose appearing in the urine, but such tests should only be considered as a test for carbohydrate tolerance, and any insufficiency shown may not show islands of Langerhans insufficiency. On the other hand, there