( 1147 ) 
according to the different parts of the spinal cord on which the 
strychnine is applied. 
If this poison is put on the caudal spinal segments, the symptoms 
are shown in the posterior portion of the body. 
If I poisoned the dorsal mechanisms of the right half of the 
intumescentia lumbalis, the syndrome manifested itself exclusively 
in the right hind-leg. 
In another case again the poison was applied on the dorsal surface 
of some of the caudal segments of the thoracal part of the medulla, 
after which the symptoms, described above, were manifested in a 
zone encircling the body like a band and passing over the most 
caudal ribs. 
From these facts it becomes evident that the syndrome may be 
localized. It is even possible, if one after another the dorsal surfaces 
of single spinal segments are poisoned, to obtain a series of skin-fields, 
within which the syndrome is manifested, differing among them 
as to form, situation, and extension. 
In this manner in a series of experiments, from 7h. XII to S. 1 
included, I have poisoned successively the dorsal mechanisms of 
every single spinal segment and by so doing I obtained a number 
of skin-tields in which the syndrome (— paraesthesia concluded by the 
biting and licking of the skin-field, hyper-reflexion, concluded by 
violent reactions if the skinfield was touched) was manifested ; 
those skinfields were placed in regular succession on the hindleg of the 
dog, their shape, situation, and extension being characteristic for each 
single zone. I will call these skinfields strychnine segmental zones. 
As an instance of the way in which I proceeded in this series of 
experiments, as regards the method of the strychnine application, as 
well as the examination of the sensibility and the defining of these 
strychnine segmental zones, the protocol may follow here of one of 
my experiments on the caudal thoracal spinal cord; the more so 
because from the adjoined figures (fig. I—IV), demonstrating the results 
obtained in two cases of defining the boundary of the strychnine 
segmental zone of 7h. X, it becomes clearly obvious how much for 
one and the same segment the zones resemble one another as to 
shape, situation, and extension. 
I have chosen this experiment also, because the strychnine zones for 
the trunk segments are very simple as to shape, contrary to those 
situated on the extremity, and therefore showing with greater evidence 
their mutual resemblance. 
