344 
ME. E. P. FRANCE ON DEGENERATIONS WHICH FOLLOW LESIONS 
pyramidal tract on the right side, triangular in shape, extending from the cornu 
outwards and forwards till it reaches the surface near the middle of the lateral border. 
The degeneration is most marked in that part which borders the direct cerebellar 
tract ; there are many degenerated fibres and considerable sclerosis. The direct 
cerebellar tiuct is encroached upon at its anterior end by the crossed jDyramidal tract 
degeneration, which spreads out, backwards and forwards, a little way along the 
circumference of the cord. 
Dorsal Region (fourth dorsal nerve).—The lateral tract degeneration comes nearer 
the circumference of the cord, and is altogether situated more posteriorly than in the 
cervical reo;ion. 
The degeneration does not invade the direct cerebellar tract in this region. 
On the opposite side there are a few degenerated fibres and some sclerosis in a 
corresponding area. 
Eighth Dorsal Nerve. —The degeneration here is less in amount than at the fourth 
dorsal; it occupies a similar position, except that it comes altogether to the surface. 
Tjumhar Enlargement. —The degeneration here is small in amount and lies in tire 
angle formed by the circumference of the cord and the tip of the posterior cornu. 
Dee’eneradion can still be seen on the other side. 
Case 10.— No. 40 of First Series. (figs. 4a, Plate 27, 46 and 4c, Plate 28. See 
also ‘Phil. Trans.,’ B, 1888, Plate 7, fig. 40b.) 
Lesion. —Bemoval of the right gyrus fornicatus, with injury to the marginal gyrus 
(fig. 4a, Plate 27). 
Frontal sections through the brain show that the gyrus fornicatus was completely 
removed, and that the lower border of the marginal, especially at the front, was 
much undermined, and thus partly cut oft' from the corona radiata. There were also 
one or twm small patches of softening on the exteimal surface. 
Result. —There was, at first, some paresis of the limbs and of the facial muscles on 
the left side. 
For ten days there was entire loss of reaction to tactile and painful impressions on 
the left side. There w'as gradual, but only partial, recovery of sensation. 
The animal died ten weeks after the operation. 
Degenerations Observed. 
Degeneration and shrinking could be seen wfith the naked eye in the pyramidal 
bundles of the pons and medulla on the right side, and in the crossed pyramidal tract 
on the left side, down the whole length of the cord. 
Pons. —Microscopically there is distinct scattered degeneration in the j^yramidal 
bundles of the |)ons. 
Medulla. —The right pyramid shows extensive degeneration and sclerosis (fig. 46). 
