have not, however, been able to find that they know, as they might readily do, and as a crow would surely do, when the weapon was loaded and when empty. They show no interest in it, such as monkeys readily display toward any mechanical contrivance to which their attention has been directed. All these negative features indicate that the mechanical side of the canine mind is entirely undeveloped. [Illustration: Collie] Although there is some evidence that the sense of number attains a measure of development in dogs, the ability to form mathematical conceptions of any kind appears to be very weak in this species. The fact that shepherd-dogs, in a way, keep an account of considerable flocks so that they will know when one is gone astray, can readily be explained on the supposition that they know their charges individually and not in sum. The absence of arithmetical capacity is, however, less important than the lack of mechanical sense, for the reason that such incapacity is also common in the lowest races of men. Although dogs, as before noted, quickly and clearly acquire a notion of property rights in all which pertains to their owner's holdings, they appear never to extend their sense of their own personal possessions beyond the original limit to which they had attained when the species was domesticated. The creature feels a sense of personal property in his food and in his sleeping-place, but appears not to extend his conception of individual rights beyond these primitively established limits. All our well-bred household dogs quickly learn certain bodily habits which are necessary to make them acceptable members of a household. These habits are not well affirmed by inherited instinct, but the ease with which the instruction is acquired shows that they have become prone to submit to such regulations. Culture on this line rests upon a primal instinct, originating we know not how, which leads a number of wild animals to conceal their excrement. On the other hand, these creatures exhibit no sense of modesty, though that, in a more or less complete measure, is characteristic of all human tribes whatsoever.