520 A. J. LINOWIECKI 



uiiniittclbar an die Kohuulosche Foi-mation, nacli iiiticii an die s'"'^*^'^ 

 Sul)stanz, niit wclclior es, vielleicht uur wcil die Elenunitc der (Jronz- 

 scliicht iioch niarklos sind, zu oinem ficniciusanion farblosen Folde vcr- 

 schniilzt. Seitwarts reicht es in seiner hinteren Hiilfte l)is zur Periplierie, 

 in seiner vorderen wird es jedoch nach auszcn von der um diese Zeit 

 sclion myelin haltigen Kleinhirnseitenstrangbahn umsaumt. 



Munzier and Wiener ('02) also located the pyramidal tract 

 in the lateral funiculus only. Ziehen, who employed the Marchi 

 stain, found degenerated fibers in the anterior and posterior 

 funiculi besides those seen in the lateral funiculus. 



In Pal-Weigert preparations the area occupied by the pyram- 

 idal tract cannot be recognized. The lateral funiculus stains 

 equally throughout. In the pryidine-silver preparations it is 

 obvious that the non-medullated fibers are very numerous, but 

 they do not stain as sharply as in the cords of other animals. 



The medullated fibers are very large in diameter and the 

 largest found measured 17.44 ^t, while the majority of these fibers 

 measured 11.3/x to 15.6 ^ in diameter. 



Cat 



The relative size of the pyramidal tract as compared with the 

 transverse area of the cord in the cat is greater than in the animals 

 already examined. Its location corresponds to that found in 

 the rabbit. It has a somewhat irregular outline, is very large 

 and is situated in the posterior half of the lateral funiculus. It 

 is in close proximity with the posterior horn and extends to about 

 2 mm. from the periphery of the cord. 



This corresponds with the findings of v. Lenhossek ('89) who 

 localized the tract by the degeneration method. He also states 

 that this tract occupies 7.76 per cent of the transverse area of 

 the cord at the middle of the cervical cord. Probst ('99), on the 

 other hand, who confined his experiments to dogs and cats, 

 states that in eleven animals he could locate a faint anterior 

 pyramidal tract. 



The pyridine-silver preparations at the level of the third cervical 

 segment show the tract stained somewhat deeper than the rest 

 of the white substance though its outline is not sharp. Lower 

 down at the seventh cervical segment and as seen in figure 4, 



