microcephalic idiot with bilateral porencephaly. 
491 
the asymmetry at once arrests attention. The inferior olivary body 
of the left side is rather smaller than that on the right side. 
The right half of the bnlb is evidently much attenuated as 
compared with the left half : and while all parts are thus affected, 
the pyramidal tract of the right side appears to be particularly 
reduced in sectional area. It is perhaps noteworthy that a slight 
but distinct degree of bilateral asymmetry is seen in the control 
section. 
Histological observations. 
For microscopic examination, portions were taken from thirteen 
different regions of the encephalon, and the internal carotid artery 
of the left side was cut in transverse section. The regions examined 
in this way are given in the following list. 
1. The right temporal region where the dilatation of the right 
lateral ventricle is greatest and where the wall of the 
ventricle is greatly attenuated on the lateral aspect. 
2. The right precuneus. 
3. The right ascending frontal gyrus (i.e. the gyrus identified 
as such). 
4. The right hippocampus with the gyrus dentatus. 
5. The left first temporal gyrus. 
6. The cortex of the cerebellum. 
7. The splenium corporis callosi and the fornix. 
8. The extreme end of the right occipital lobe. 
9. The region of the forceps major in the left hemisphere. 
10. The right crus cerebri and right optic tract. 
11. The lowest part of the mid-brain at the commencement of 
the pons varolii. 
12. The bulb : at the upper end of the inferior olivary body. 
13. The bulb : just below the inferior olivary bod}^. 
14. The internal carotid artery. 
In the following paragraphs the chief appearances presented 
by sections from these regions are briefly described. 
1. The right temporal region. 
The section passes in a vertical plane transversely to the long 
axis of the hemisphere, and cuts through the infero-lateral border. 
Owing to the dilatation of the lateral ventricle, the wall of the 
hemisphere is extremely attenuated, and does not exceed 3 mm. 
in thickness. The following features were observed. 
(a) The whole tissue is infiltrated with innumerable droplets 
of amyloid substance. The droplets are especially numerous in 
the intermediate portions of the section, less plentiful on the 
ventricular aspect, and least so towards the external or superficial 
aspect. 
