22 GENERAL PART 



glands and the suprarenal cortex, which are both of such importance for the 

 development of the secondary sexual characters and stand in immediate 

 relation to premature development, both develop from the celomic epithelium. 

 From this standpoint it would be interesting to see whether in eunuchs the 

 suprarenal cortex is not hypoplastic. I am well aware that this grouping of 

 the ductless glands is associated with much that is speculative, but never- 

 theless it seems to me that their study in this direction is of practical value. 



Grouping of the Ductless Glands 



Let us now attempt a classification of the ductless glands according to 

 their physiological actions. I first attempted such a classification four years 

 ago, in which I differentiated acceleratory and retarding hormones. This 

 differentiation was founded on observations as to the in many respects an- 

 tagonistic influencing of the metabolic processes through the hormones or 

 ductless glandular extracts. Biedl later used the terms dissimilatory and 

 assimilatory for them. We can also say catabolic and anabolic. This 

 division cannot be carried out for the totality of the ductless glands, yet it 

 seems to me one well adapted for its purpose. I quote the following examples : 



The hormone of the thyroid gland we may regard with full right as ac- 

 celeratory or dissimilatory or catabolic. As far as we know its actions, 

 it quickens metabolism and increases excitability. That in absence of the 

 thyroid in early youth growth and assimilation remain behind does not seem 

 to me to speak against this assumption, for the arrest in growth is to be re- 

 garded only as the effect of serious inhibition of all metabolic processes. 



Also the hormone of the chromaffin tissue is of pronounced acceleratory 

 or catabolic action. It increases the excitability of the sympathetic nerves 

 decomposes glycogen, increases the respiratory metabolism, etc. (the more 

 intense formation of glycogen in the course of a chronic adrenalinizing I 

 regard as only a secondary one, through compensatorily increased activity 

 of the pancreatic insular apparatus) . 



Again, the posterior lobe of the hypophysis belongs to this group of duct- 

 less glands, at least we must regard the actions of the pituitrinum infundi- 

 bulare as pronouncedly catabolic or dissimilatory. 



To this group we may oppose the glands with retardative or anabolic 

 or assimilatory hormones. To the latter belong the pancreatic insular 

 apparatus, that controls the building up of glycogen and also the assimilation 

 of fat, and diminishes the excitability of the sympathetic nerves (Lowi)\ 

 further the parathyroid glands, that probably assist the assimilation of cal- 

 cium in the ganglion-cells and at the same time reduce their excitability. 

 Both work assimilatory and excitability-diminishing, each however in a 

 specific way; cataract formation may accompany deficiency of either. 



Probably to this group belongs also the anterior lobe of the hypophysis, 



