VII 

 THE DUCTLESS GLANDS 



UNDER the heading of the ductless glands are included the 

 hypophysis (pituitary body), the thyreoid, the parathyreoids, 

 the glomus caroticum (carotid body), the thymus, the spleen, 

 the supra- renals and the glomus coccygeum (coccygeal body). 

 It must be remembered, however, that many of the glands 

 which possess ducts do not excrete all their secretion through 

 these ducts, and that a part of their secretion is carried away 

 by the blood-stream. In this way, the ovary, testes, pancreas, 

 etc., all behave after the manner of ductless glands. Further, 

 although, like other parts of the body, they are subject to 

 numerous pathological changes, the nature of their secretions 

 may be so changed as to alter their controlling influence with- 

 out producing any recognisable change in the gland itself. On 

 the other hand, such grave conditions as exophthalmic goitre 

 and splenic anaemia are accompanied by striking alterations 

 in the glands concerned. 



The Hypophysis (Pituitary Body). The hypophysis 

 lies in a fossa on the superior aspect of the body of the 

 sphenoid. Above, it is attached by a small stalk to the tuber 

 cinereum in the interpeduncular fossa (p. 16), and it is 

 partially roofed in by a small process of dura mater (Fig. 56). 

 This connexion with the brain indicates in part the develop- 

 ment of the gland, for its posterior lobe develops as a down- 

 growth from the floor of the third ventricle. The anterior 

 lobe develops as an up-growth from the roof of the pharynx, 



with which it soon loses all connexion. It was formerly 



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