Page:Popular Science Monthly Volume 1.djvu/361

Rh into a revolving motion, and turns on himself like a ball. The former movements are chiefly produced by lesions of the encephalon, and were obtained very neatly in a frog from which were removed the cerebral lobes of the left side. The movements were made from the left side toward the right.

What fixed attention at first in the attitude of this frog was, that all the right part of the body had the carriage and aspect of a frog without a cerebrum (Fig. 2). The hind-foot of this side approached the body more, and was gathered in a heap, as shown in Fig. 3, while the fore-foot was equally drawn up, and had the position that we have



seen to be constant in frogs in which the cerebrum had been removed.

At the same time, the entire animal leaned a little to the right side. This inclination of the body is neither constant nor inevitable with animals which have only the movements in a circle; it is, on the contrary, constant and forced with those that have the turning motion.

The attitude of this frog changed, and was even reversed, when it