Among mammals generally, except the tendency to greater pugnacity shown by the male towards other males, and the greater solicitude for the young shown generally by the female form, but not always; the psychic differences between the two sex forms are not great. Between the male and female pointer as puppies, there is as little difference in mental activity as in physical; and even when adult, on the hunting ground, that great non-sexual field in which their highest mental and physical activities are displayed, there is little or nothing which distinguishes materially between the male and female; in method, manner, and quickness they are alike; in devotion to man, they are psychically identical. (It is often said the female dog is more intelligent than the male; but I am almost inclined to doubt this, after long and close study of both forms.) It is at the moment when the reproductive element comes fully into play that similarity and identity cease. In the intensity of initial sex instinct they are alike; the female will leap from windows, climb walls, and almost endanger her life to reach the male who waits for her, as readily as he will to gain her. It is when the bitch lies with her six young drawing life from her breast, and gazing with wistful and anguished solicitude at every hand stretched out to touch them, a world of emotion concentrated on the sightless creatures, and a whole body of new mental aptitudes brought into play in caring for them, it is then that between her and the male who begot them, but cares nothing for them, there does rise a psychic difference that is real and wide. Alike in the sports of puppydom and the non-sexual activities of adult age; alike in the possession of the initial sexual instinct which draws the sex to the sex, the moment active sexual reproduction is concerned, there is opened to the female a certain world of sensations and experiences, from which her male companion is for ever excluded.