TWELFTH LECTURE. 



GLAND TISSUE. 



In olden times they were very liberal in their conception 

 of the glands. We have already learned this in the lym- 

 phoid organs, as well as the thyroid gland, suprarenal capsule 

 and apophysis cerebri, which preceding generations of anato- 

 mists erroneously regarded as glands. A rounded, limited 

 form, and a considerable vascularity was at that time suffi- 

 cient to stamp a thing as a gland. We thus obtained the 

 lymphatic, Peyerian, and thyroid glands, etc. Later, the 

 physiological importance came more into the foreground. 

 The true glands take materials from the blood, not alone or 

 only principally in the interest of an egotistical nutrition, but 

 rather in the service of the whole, whether it be to simply 

 free the blood from decomposed substances, or to restore the 

 latter, more or less metamorphosed, and serving for other pur- 

 poses. On this rests the old distinction of excretion and 

 secretion. 



The gland requires an efferent canal system to remove its 

 contents. We must lay great weight on this canal in connec- 

 tion with the gland ; still the former may, under certain cir- 

 cumstances, be wanting, or may remain separate from the 

 organ. This is shown by the human ovary. Here the wall 

 of the glandular cavity is ruptured. The contents of the lat- 

 ter now escape through a rent. It does not thereby cease 

 to be a gland, for we know of ovaria- enough in lower ani- 

 mals which contain quite common glandular formations, pro- 

 vided with continuous canals. 



No doubt can therefore prevail here. 



How weak the matter is, however, with the so-called 

 blood-vascular glands has already been taught by the previ- 

 ous lecture. 



