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segment ot the medulla isolated in this latter way, might wholly 
independently continue to be capable of reflexive function, and a 
few years ago I succeeded, basing upon former investigations, to find, 
as has been related elsewhere *), that in the toad (Bufo vulgaris), a 
small portion of the medulla, encompassing approximatively the 
irradiating zone of the 2ed nerve-root of the medulla (= 1st nerve 
of the arm), continues to be capable of provoking reflexive reactions, 
even when the whole remainder of the central nerve-system had 
been destroyed. 
At present I am enabled to relate the results of investigations 
made on dogs. These experiments were taken in the following manner. 
On a dog, preferably a young one, that had been put into morphia- 
chloroform-ether-narcosis, the medulla in the thoracal-lumbar region 
was opened over a length of at least seven segments. Next, without 
opening the dura meninx, to the right and to the left at least three 
pairs of nerve-roots were cut through from foreward to backward, 
one pair of roots was left intact and below this latter, three or more 
others were cut through on both sides. The wounds in skin and 
muscle were then provisionally suturated by a few sutures, and the 
moment was awaited that the animal would be sufficiently awakened 
from the nareosis to react when the skin was excited by painful 
stimuli. Then, by means of the usual method (pinching), to the right 
and to the left on the trunk the skin-fields, that had become anal- 
getie in consequence of nerve-roots having been cut through, were 
defined as to their situation, their shape and their extension, and 
likewise the sensible area lying between these former and corresponding 
to the region innervated by the uninjured root (dermatoma). The 
boundaries thus found, were traced as usually with a pencil. 
After this the dog was once more put into narcosis, the suturating 
was unfastened and the medulla opened anew, the dura mater of 
the segment containing the uninjured pair of roots was cut open 
and the course of the fascicles of nerve-fibres in it carefully observed, 
after which the medulla was quickly cut through, a little space 
before the place of entrance of the most cranial fascicle and a little 
space behind that of the most candal fascicle, and some warm 
moistened ganze was put upon the wound in order to prevent 
hemorrhage. The narcosis was stopped immediately afterwards, and 
the investigations began to discover what reflexive funetion might 
eventually have been retained. 
In a series of similar experiments | have found, that whenever 
1) Folia Neurobiologica. HI. 6. 718729. Leipzig. 1909, 
