. The common frog. Frogs. VIII.] THE COMMON FROG. 115 fluid be applied to a spot easily reached by one foot, the decapitated frog will apply that foot to the spot. More than this, if that foot be cut off it will move the stump as before, seeking to reach the spot and failing so to do, will then apply the other foot to the irritated locality. These, and such experiments, are of course con- clusive, if the common assumption be conceded that the brain is the indispensable nervous instrument of Fig. 71.—The Brain of Man as seen when a \'ertical Longitudinal Section has been made throug
. The common frog. Frogs. VIII.] THE COMMON FROG. 115 fluid be applied to a spot easily reached by one foot, the decapitated frog will apply that foot to the spot. More than this, if that foot be cut off it will move the stump as before, seeking to reach the spot and failing so to do, will then apply the other foot to the irritated locality. These, and such experiments, are of course con- clusive, if the common assumption be conceded that the brain is the indispensable nervous instrument of Fig. 71.—The Brain of Man as seen when a \'ertical Longitudinal Section has been made through its middle. Av, arbor vitae of the cerebellum; c, cerebrum; cc, corpus callosum ; cq, corpora quadrigemina ; f, fornix (between the fornix and the corpus callosum is the septum lucidum); in, medulla oblongata ; ina, corpus mammillare ; on, optic nerve ; //, pineal gland ; pt, pituitary body; pv, pons Varolii; o, soft or middle commissure. It is possible, however, that the faculty of sensa- tion may be subserved by the spinal cord without the brain, and if so, all these much vaunted experiments are valueless as regards the truth of pure reflex action, not but that they are of extreme interest, as showing what may be done in lower animals without the intervention of any brain action what- ever. I 2. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Mivart, St. George Jackson, 1827-1900. London, Macmillan and co.
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