. 72 FIELDING H. GAKRISON 



been advanced. The first is the doctrine of the hormones of Bayliss and 

 Starling (&)*(1902), i n which the chemical regulation of the body is as- 

 sumed to be effected by means of hormones, or chemical messengers, which 

 pass from the various organs and ductless glands, via the blood-stream, to 

 other parts of the body, producing biochemical effects upon irritable proto- 

 plasmic tissues. Hormones are of two classes, those which excite the func- 

 tions of organs containing involuntary muscle, and those which regulate 

 morphogenesis, the latter being known more specifically as hormazones 

 (Gley). In the initial experiment of William M. Bayliss and Ernest Henry 

 Starling (a), the secretion of pancreatic juice following upon introduction 

 of acid into the duodenum was found to be, not a local reflex, as had hith- 

 erto been assumed, but due to the action of a hypothetical substance (se- 

 cret in) discharged by the intestinal mucous membrane under the influence 

 of the acid and carried to the pancreas by the blood channel. As Keith 

 expresses it, this experiment demonstrated that there is a postal system in 

 the body via the blood channels, in addition to the telegraphic system via 

 the nerves. Adrenalin, iodothyrin, and pituitrin are the only hormones of 

 the ductless glands which have been isolated to date. 6 



The other theory is that of the clinicians and pharmacologists of the 

 Vienna school, Hans Eppinger, Wilhelm Falta, and Nicolaus Riidinger, 

 which asserts that the suprarenal and thyroid bodies act upon and are con- 

 trolled by the nerves of the sympathetic system, while the pancreas is 

 similarly related to all nerves acting upon smooth (involuntary) muscle 

 and not originating from the chain of sympathetic ganglia. The two sys- 

 tems of nerves have been termed "autonomie" by Langley, because they 

 seem to be detached from and independent of the controlling impulses aris- 

 ing from the cerebrospinal axis, while themselves controlling all organs 

 containing unstriped muscle, secreting glands, or both, e. g., the smooth 

 muscle of the bronchi, stomach, intestines, blood vessels, genitalia, eye, and 

 all the glands of external and internal secretion. The sympathetic or 

 visceral nervous system lias also been called the "vegetative" system, be- 

 cause the organs under its dominion functionate involuntarily or uncon- 

 sciously, as with vegetables or plants. While some authors have limited the 

 term "vegetative system" (autonomie system of Langley) to the thora- 

 co-lumbar autonomie, which originates from the sympathetic ganglia, 

 others include under this designation the whole visceral nervous system, 

 i. e. ; both the cervico-thoraco-lumbar autonomie (sympathetic system) and 

 the antagonistic system governing involuntary muscle, which is largely 

 made up of fibers from the vagus nerve and is now styled the crania-sacral 

 or "vMiial antonomic.' 1 7 



"That iodolliyriii an.l pituitrin are actual hormones is doubtful, though each may 

 contain hormones. Kendell's thyroxin is rather more probably a pure hormone than 

 i-ilher of these. H. (J. U. 



l.inrley's own division of the entire autonomie system into sympathetic and 

 asympathetic components has much to commend it. R. G. H. 



