1 66 SCIENCE PROGRESS. 



dilatation, he inferred that the sympathetic and chorda have 

 direct frigorific and thermogenic actions respectively. 



Morat finds that, after elimination of the vascular modi- 

 fications, excitation of both the glandular nerves produces 

 a rise of temperature, a result that is consonant with the 

 fact that both are secreto-motor nerves. Proceeding to 

 look for a frigorific effect of an inhibitory nerve, he 

 examines the effect of vagus excitation on the temperature 

 of the cardiac muscle, and finds, as was to be expected, 

 that depression or arrest of the beats is accompanied by a 

 fall of temperature. 



In Germany the search for inhibitory effects has been 

 pursued mainly in consequence of the impulsion of Hering's 1 

 well-known doctrine of assimilatory and disassimilatory pro- 

 cesses, first in the retino-cerebral apparatus, then in all tissues; 

 the search has been directed more especially to the volun- 

 tary muscles and nerves of the lower animals and of man 

 himself. Biedermann's experiments on the claw of the 

 crayfish and on veratrinised frog's muscle — Kaiser's glycer- 

 ine experiment on the frog's sciatic — Wedensky's observa- 

 tions also on the frog's sciatic — the investigations of Fick, 

 of Mosso and of Waller on human nerve and muscle, contain 

 data bearing more or less closely upon the question. It is 

 also touched upon by the experiments re dilatation of the 

 pupil, by Heese and by Langley and Anderson, and by 

 an observation of Sherrington's with regard to movement 

 of the eyeballs. We might also have mentioned the obser- 

 vations of Orchansky, but that the question of central in- 

 hibitory phenomena is too extensive to be properly included 

 in this brief article, which is intended to cover only the 

 question of peripheral inhibitory phenomena. 



Biedermann's observations are now generally known ; 

 they need, therefore, merely be attended to as among the 

 first definite data giving body to the floating notion of 

 motor states, antagonised and overcome by anti-motor pro- 

 cesses consummated in the muscle itself. The main point 



1 Hering, Zur Tlicorie der Vorgange in der lebendigen Substanz. Prag., 

 1888. 



