INTERNAL SECRETIONS 93 



history. It is a round body, the size of a small marble, which 

 occupies a deep recess in the floor of the skull, beneath the 

 centre of the brain. It is composed of epithelial cells col- 

 lected into irregular groups. No homologue of the pituitary 

 body can be found in the invertebrate sub-kingdom. Its 

 strange mode of development in vertebrate animals it is 

 present in them all, from fishes to mammals and the mystery 

 in which its prevertebral existence is hidden, provoke to specu- 

 lation. We must be content to state that it is undoubtedly 

 masquerading under an assumed name. " Pituitary body " 

 is reminiscent of a long-abandoned theory that it secretes fluid 

 into the upper chamber of the nose. 



Disease of the pituitary body is associated with a perversion 

 of growth even stranger than that due to disease of the thyroid 

 gland. The condition has been termed " acromegaly," to 

 indicate that all extremities toes, fingers, nose, lips, tongue 

 undergo enlargement. 



With these three organs the thyroid gland, the suprarenal 

 capsules, and the pituitary body we must leave the subject 

 of internal secretions. Each of these organs is a ductless 

 gland. Each has a history which the zoologist is unable to 

 transcribe. The document is a palimpsest, the earlier script so 

 faint as to be illegible beneath the dark letters which a new 

 era has written over it. Even the modern script is smudged 

 and blotted. The laws which it sets forth seem, as a rule, to 

 be destitute of sense, but a sinister meaning is evident at 

 times. We are tempted to regard these codes as obsolete, 

 until the mischief which follows their suppression calls our 

 startled attention to the fact that they are, in the most lively 

 sense, extant. Myx oedema, Addison's disease, acromegaly, 

 are ominous warnings that the three ductless glands are no 

 mere monuments of a past epoch, which owe their survival 

 to Nature's indolence. They teach us that we must not 

 attribute the persistence of such organs to a conservatism 

 which resists innovation, or suppose that they would long 

 ago have been wiped off the statute-book if her inertia could 

 have been overcome. Undoubtedly Nature gives us many 

 excuses for adopting this attitude of mind. The " chest- 

 nuts " on a horse's legs, the " dew-claws " of a dog's foot, 

 are vestiges which would have disappeared if every part of 



