In some _Felidæ_, such as the Domestic Cats, the pupil, or small aperture in front of the eye which lets in light to the sensitive retina beyond, has the round shape it possesses in man, only in the dark, when it is dilated to receive every ray of light available. In the day, on the other hand, when more light is to be had than the animal requires, the pupil contracts to an ellipse, or in the strongest light to a mere line. This is not the case in the larger Cats, such as the Lion, Tiger, and Leopard, in which also the eyes themselves and the cavities in the skull for their reception are smaller, proportionally, than in the Domestic Cat. Taking the structure of the Cat tribe, all in all, there is nothing whatever to make it the least difficult to suppose that they all sprang from one stock, and that size and colour, and every other point in which they now differ from each other, may have been brought about, through long periods of time, as the result of the influence of their surroundings. It is necessary to presume this, for classifiers from necessity lay hold on the most minute differences, for the sake of making proper specific distinctions, although these differences may be merely the outcome of some change of locality, warmer, or colder, drier, or moister, higher upon the hills, or lower down on the plains. Once developed, however, it becomes hereditary, and then a _variety_ becomes a _race_, and a race solidifies into a _species_. Yet, the result once obtained, however it arose, the profit is great to us who are careful observers and enthusiastic admirers of the infinite fecundity of Nature. CHAPTER II. THE CAT FAMILY--THE LION. THE LION--Its Geographical Distribution at the Present Day and in Ancient Times--Its Haunts--Varieties of the Lion--Distinction between the Lion and other Cats--Its Courage, Speed, and Strength--Its Roar--Its supposed Magnanimity--Its Habits--Man-eating--Occasional resort to Vegetable Diet--Love-making--The Lion-cubs and their Education--Old Age--Breeding in Captivity--Lion-hunting. THE LION.[7]