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This figure makes us already surmise that part of each dermatome 
ean be covered by more than one. For this reason I have determined 
rows of adjoining dermatomes with different cats. | found then, that 
three dermatomes from the thoraco-lumbal region have a rather 
large strip of skin in common; this strip which is rather narrow 
at the dorsal median line, ventrally increases in width. 
In this way I determined of the cat, represented from the dorsal 
side in Fig. 2 and from the ventral side in Fig. 3, the dermatomes 
of thoracalis 12 and 13 and lumbalis 1, 2, 3 and 4. T obtained 
these six dermatomes, by always cutting the hind-root of the 
indicated dermatome and then determining the adjoining dermatome 
according to the strychnine-method. So I obtained a series of lines 
on the skin as boundaries of the dermatomes in such a way that 
every time both the anterior and the posterior boundary of each 
dermatome moved a little farther. At the ventral side (Fig. 3) I 
have made white a part that is covered by + dermatomes. In order 
to elucidate these figures I have made an entirely finished prepara- 
tion of that part of the skin on which these dermatomes occur, and 
made a sketeh of the extended figure of the skin. This sketch is 
represented in Fig 4. I have indicated the anterior and the posterior 
boundary of each dermatome on the dorsal side by the figures that 
indicate the roots. If now we examine the covering of the field of 
lumbalis 1, we find the part that is indicated by transversal dashes 
covered by lumbalis 2 and thoracalis 12 and 13. The piece indicated 
by longitudinal dashes is only covered by thoracalis 13. The other 
part of the dermatome of lumbalis 1 is partly. covered by one, 
partly by two dermatomes. 
We see likewise in this representation, that the dermatomes of 
lumbalis 3 and 4 deviate especially in the ventral part considerably 
in a posterior direction. Here we receive indeed the impression as 
if through the development of the hindlegs these dermatomes have 
been drawn backward. (SHERRINGTON). The anterior boundary of 
lumbalis 3 cuts consequently the posterior boundaries of 1 and 2. 
It is to be attributed to this fact, that these two dermatomes cover 
in the ventral part those lying in front of them less completely. 
Moreover I found, that in the middle of the trunk the covering 
of the ventral side is strongest. We see in this figure that thoracalis 
12 and lumbalis 2 have one strip in common beginning at the 
lateral side and widening ventralward. It appears consequently 
that dermatomes not covering each other dorsally can do so to the 
ventral side. Measurements of the mutual covering of these 6 root- 
fields taught me that at the dorsal medianline: 
