The psychic development of young animals and its physical (somatic) correlation with specific reference to the brain / by Wesley Mills.
- T. Wesley Mills
- Date:
- 1896
Licence: Public Domain Mark
Credit: The psychic development of young animals and its physical (somatic) correlation with specific reference to the brain / by Wesley Mills. Source: Wellcome Collection.
Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.
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![of voluntary niovemonts and the speedier perfection attained by each, together with the more ready and complete utilization of experience, the early intelligence, the strength of the will and the power of attention. All this is correlated with that earlier development of the cerebral cortex which I have shown occui-s in the cat, and there i.s probably a greater difference than can be made manifest by our crude methods of experiment. A very marked feature in the psychic development of the cat is the early appearance of the play instinct' and the [lerfection of the fore-limb in carrying out the movements necessary for its manifesta- tions. The cat has incomparably better use of the fore-limb at an early ilate. I have recorded observations on play (with use of the paws), as early as the twenty-second day, and, as is well known, the kitten and the older cat have a variety and perfection of movement of the fore-limbs never acquired by the dog. This is distinctly correlated with brain development, for, as 1 have iminted out, movements of the fore-limb are in the cat the first that can be induced by electrical excitation of the cortex, and to this observation my experience leads me to believe there are practically no exceptions, while the case is very different for the dog. Some investigators have expressed the opinion that the fore-limb is also the first to respond in the dog, l)Ut this does not accord entirely with my experience. It has occasionally been so i»i the j)up])ies on which I experimented, but in the large majority the liind-leg responded first. .Mongrels and pure-bred animals of different varieties were us<id. 1 do not, tbereforo, Udieve that the statement that the fbre-leg in the dog is always the first to respond to electrical excitation can any longer be maintained as a sound generalization ; but it may be as 1 have suggested in my ])aj)er on the brain that the truth is that sometimes the one and sometimes the other limb is tbe first to react, and that large allowance must be jnade in any general statement for individual and breed differences. III.—The Eabbit. Sucb a creatiu’e as the rabbit contra.sts in the most mark(‘d manner with the dog and the cat. A rabbit to the last is much more a creature of instincts and reflexes j)ure and simple with relatively but little intelligence, all of which is in harmony with its simple modes of existence. Its food is in the wild state usually abundant, and as its esca])e from enemies is accomplished by swiftness in flight or by taking refuge in its burrow, there is little in its environment to develop intelligence. With the carnivora it is quite otherwise. They obtain their food by cunning, stealth, stratagem—it may be concerted action, as in the case of wolves, hyaenas, wild dogs, etc. > The whole suljjecfc of play in animals is e.xhaustively treated by Dr. Karl (irons in his “ Die Spiele der Thiere. Gustav Fischer, Jena, 1SD6.](https://iiif.wellcomecollection.org/image/b22471650_0008.jp2/full/800%2C/0/default.jpg)
