686 SCIENCE PROGRESS 



the blood pressure. The biological significance of this has been so well expressed 

 by Elliott in the Sydney Ringer Lecture that I will quote a passage in support of 

 my argument. 



"Morphology therefore tells the same tale as physiological analysis. The 

 adrenalin cells and the sympathetic nerves belong to a common system, whose 

 first duty is that of sustaining the activities of the circulatory muscles. As the 

 animal develops its muscular efficiency, learns a hundred new functions, and with 

 a constant body temperature becomes independent of its environment, the sym- 

 pathetic system becomes more and more complex, and is split up into manifold 

 possibilities of delicate adjustment. All these are but refinements of means for the 

 one great end — to enable the animal to move more swiftly, to catch its prey, and 

 to fight. Fighting power rises with the rise of blood pressure, reserves of sugar 

 to feed the muscles are hurried up from the liver on the call of the circulating 

 adrenalin, the daily routine of digestion is checked by intestinal inhibition, and 

 the various segments of the bowel are cut off from one another by the closure of 

 the sphincters. Cannon has reiterated this view and, further, shown very neatly 

 how the clotting of blood by adrenalin, which had been observed by myself and 

 others, is a further elaboration to check leakage in any chance wound of the body 

 during action. 



" By that curious antithesis of the emotions upon which Charles Darwin laid 

 stress, the machinery employed to prepare for fight may, with the cowardice of 

 civilisation, be set as powerfully in motion only to express fright. And in this the 

 adrenalin is equally, or perhaps even more, exhausted." 



It is difficult to follow Elliott in this latter argument, for if it requires prolonged 

 fright to exhaust the supply of adrenalin, its escape into the circulation of an 

 animal that relies upon flight is as necessary for preservation as it is in one that 

 relies upon fight. Carnivora may, under certain conditions, rely upon flight just 

 as herbivora may upon fight for preservation. 



The raw material or inborn tendencies of the foundations of character are a 

 complex dependent upon species, sex, and race, which have been fixed by the laws 

 of evolution and have structurally organised, and are therefore capable only of 

 comparatively little variation ; grafted on this stock are the inborn dispositions 

 and tendencies dependent upon racial amphimixis and the more mutable and less 

 stable individual dispositions and tendencies derived by ancestral variations and 

 modifications. These " characters of dispositions impressed by nature/' and the 

 study of which Bacon found wanting, form the raw material of individual 

 character. The same primitive emotions, instincts, appetites, and desires are 

 common to all the higher animals. These are the source of spontaneous attention 

 and of all habitual actions connected with the preservation of the individual and 

 the species, poetically expressed by Schiller in the following lines : 



" Durch Hunger und durch Liebe 

 Erhalt sich die Weltgetriebe." 



The stimulus to action is fundamentally bio-chemical, and if there is one fact 

 more firmly established than another in regard to bio-chemical influence of 

 hormones in respect to the emotions and instincts connected with the preservation 

 of the species, it is in relation to the sexual glands. There is abundant experi- 

 mental evidence and observation showing that, from birth onwards to puberty, an 

 internal secretion of the sexual glands escapes into the blood which excites and 

 makes dominant the corresponding secondary sexual bodily and mental charac- 

 ters ; and that without this internal secretion these distinctive characters of body 

 and mind are modified or wanting. 



