糖心app官方版The number at present in the Tower exceeds a hundred, varying from four to six feet in length, and differing very considerably from each other both in colour and markings.

The very terms of the specific character by which Linn?us attempted to distinguish the domesticated from the other dogs, “the tail curved upwards (towards the left),” may be regarded as affording in themselves a sufficient proof of the difficulty of the task, when so great a naturalist, after taking a complete review of all the particulars of their organization, was compelled to rest contented with a distinction drawn from so trifling and apparently insignificant a remark. It would in fact appear to be absolutely impossible to offer in any form of words whatever a character sufficiently comprehensive to combine the almost infinite varieties of this Protean race, and at the same time to separate them from those other races from which they are generally believed to be specifically distinct. To this observation of Linn?us almost the sole addition that has been made by later zoologists consists in a remark of M. Desmarest, that whenever a spot of white is found upon any part of the[86] tail of a domestic dog, the

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frequently turns completely white, a change which also takes place in many other animals inhabiting the polar regions.
Plyctolophus sulphureus. Vieill.