ON THE FUNCTIONS OF THE CEREBRAL CORTEX. 
33 
irritation caused by this may have conduced to the strongly marked contracture of 
the muscles of the opposide side. 
The brain was sliced as a whole, and four sections through the lesion are represented 
in figs. 2lA, B, c, and D. These serve to illustrate the localisation and completeness 
of the removal. 
22. 
Lesion. — Removal of both marginals in two operations. 
Results. — Tlie first operation (on left side) produced the usual paralysis of the 
opposite hind-limb, which was dragged in progressing and hung down when the 
animal perched upon a bar. All the other symptoms distinctive of this lesion are 
also observed (see p. 14). 
The second operation was performed on the eighth day after the first, the wound in 
the meantime having completely healed and the Monkey being perfectly well. The 
result of the second operation was to produce, as usual, paralysis of trunk and legs, 
except that the hips could be flexed and the knees extended (feebly on both sides, but 
more on the right side than on the left). The tail was rendered motionless. The body 
was propped upon and dragged forward by the fore-limbs. No deficiency in sensibility 
could be determined. Later, rigidity developed in both legs and in the tail, which was 
stiffly flexed over the spine. This Monkey was kept three months. Although its 
movements became much more active after £ome time than at first, this was due to 
the exercise of the unaffected muscles ; there was no recovery in those in which 
paralysis had been produced by the operation. 
The brain of this animal, which died in Long Vacation time, was injured on 
removing it from the skull, so that no drawings could be made to show the extent 
and depth of the lesion ; but there is no doubt, from the notes made at the operations 
as well as from the symptomiS, that it involved the posterior two-thirds of both 
marginal gyri, and was somewhat less complete on the left side than on the right. 
23."' 
Lesion. — Excision of both gyri marginalest at one sitting. 
Result. — The usual symptoms produced by this lesion, i.e., complete paralysis of 
trunk and almost complete of legs, but with power to flex hips. Drags itself about 
by arms. Unable to sit up, but props itself up by aid of arms. 
The animal lived four weeks after the operation. 
The lesions are represented in figs. 23 R. and l., Plate 3. 
24. 
First Lesion. — The whole of the left occipital lobe was removed by an oblique 
incision along the parieto- occipital fissure. The piece removed included the extremity 
of the posterior cornu of the lateral ventricle, which was thus freely opened. No 
* Shown to the Neurological Society, 
t That is, that portion of them shown to he excitable. 
MDdCCLXXXVIII. — B. F 
