hg HENRY O. FEISS 
(Experiments 68 and 73) that the bladder centers are higher than 
the anal centers. Sphincteric centers are very close to tail cen- 
ters (5th dural exit). 
F. Conclusion. Inferences cannot be drawn for every point 
investigated, but there is significance to certain isolated facts, 
such for example, as pertains to the relative isolation of the exter- 
nal popliteal and internal popliteal centers, suggesting perhaps 
that these nerves, which on account of their individual spheres 
of distribution control the best codrdinated joint movements, have 
their nuclei relatively best defined. The main suggestion is that 
the grouping of cells seems to correspond at least roughly to the 
gathering of fibers in individual peripheral nerves. 
Comparison of above inferences with current views on the subject 
As regards the cases where preservation of voluntary control 
in certain muscles seemed to depend on paths in the anterior 
columns, which alone were open, other experiments are on rec- 
ord,® which show that in dogs and other animals, these columns 
do convey motor fibers from the brain. There is also the possi- 
bility of the employment of paths on the contralateral side (cf. 
Part 1) and in one of our cases (Experiment 69) this seems to 
be the only explanation for preservation of control of the paw, for 
the lesion had blocked all the homolateral paths higher up. 
With reference to the knee jerk our localization in the 5th and 
6th lumbar segments corresponds to Sherrington’s more accurate 
findings.7 
As to sensations, anal reflex and relative warmth of the paws, 
our findings are too few to be entitled to colligation with those 
of others. 
The most important question that we have to consider is the 
significance of the cell-groups in the grey matter of the cord. 
Three methods have been previously used to investigate this 
point, the first being that of direct stimulation of spinal roots. 
The findings depend on the presumption that the cells of origin 
6 Bechterew: Functionen der Nerven Centra, 1908, vol. 2, p. 667. 
7 Sherrington: Schaefer’s Text-book of Physiology, 1900, vol. 2, p. 874. 
