PARALYSES IN DOGS tS 
The significance of cell-groups in the grey matter of the spinal cord 
According to different authors, the cell-groups in the gray matter 
of the cord are variously supposed to represent muscles, peripheral 
nerves, primary metameres or movements (as in the cortex). 
After a rather careful.scrutiny of some of the literature, beside 
that mentioned above, we feel that in the present state ofour 
knowledge, there is not sufficient evidence for any of these explan- 
ations. It is by no means certain that these cell-groups have 
any physiologic significance whatever. According to Knape, as 
above shown, and according to our own experiments, the findings 
seemed to point somewhat toward the peripheral nerve theory. 
Another piece of evidence for this theory is the fact that some of 
the cranial nerves have their cells of origin grouped in fairly well 
circumscribed nuclei. But neither is this analogy, nor the other 
evidence which we have cited, of sufficient weight to carry con- 
viction. If the grouping of cells in the cord is ever susceptible 
of explanation, much further investigation will be required. 
PART 38. NERVE FUSION ATTEMPTED IN THE CAUDAS AND THE 
SCIATIC NERVES IN ANIMALS PARALYZED BY MECHAN- 
ICAL LESIONS IN THE SPINAL CORD 
This part of the research is based on eight cases, the only ones 
in which the animals survived both the original spinal lesion and a 
secondary ‘fusion’ done some time after they had reached per- 
manent states in their paralyses. 
~The aim of the procedure 
Nerve fusion, it has been stated, consists simply in uniting two 
or more nerves by tying them together with absorbable ligatures. 
In the preliminary report?? the theoretical basis for this procedure 
is given, the important point being that the direction of fibers 
regenerating in scar is governed by conditions offered by the mass 
of proliferated cells and nuclei which are here formed. As these 
are laid down in all directions the new fibers which develop in 
the interstices of the cells must grow accordingly. Therefore it 
29 Feiss: Boston Medical and Surgical Journ., May 11, 1911. 
