The Duck-billed Platypus (_Platypus anatinus_) was the name assigned to one of the most remarkable of known animals by Shaw, who had the good fortune to introduce it to the notice of the scientific world in the _Naturalist’s Miscellany_ (vol. x., 1799). In the following year it was independently described by Blumenbach (_Voigts Magazin_, ii. p. 205) under the name of _Ornithorhynchus paradoxus_. Shaw’s generic name, although having priority to that of Blumenbach, could not be retained, as it had been used at a still earlier time (1793) by Herbst for a genus of Coleoptera. _Ornithorhynchus_ is therefore now universally adopted as the scientific designation, although Duck-billed Platypus or Duck-bill may be conveniently retained as a vernacular appellation. By the colonists it is called “Water-Mole,” but it need scarcely be said, its affinities with the true moles are of the slightest and most superficial description. Until the last few years the early stages of the development of the young were not fully known. It had, indeed, been repeatedly affirmed, in some cases by persons who have had actual opportunities of observation, that the Platypus lays eggs; but these statements were generally received with scepticism and even denial. This much-vexed question was, however, settled by the researches of Mr. W. H. Caldwell in 1884, who found that these animals, although undoubtedly mammals throughout the greater part of their structure, are oviparous, laying eggs, which in the manner of their development bear a close resemblance to the development of those of the Reptilia. Two eggs are produced at a time, each measuring about three-fourths of an inch in its long, and half an inch in its short, axis, and enclosed in a strong, flexible, white shell. The Platypus is pretty generally distributed in situations suitable to its aquatic habits throughout the island of Tasmania and the southern and eastern portions of Australia. Slight variations in the colouring and size of different individuals have given rise to the idea that more than one species may exist; but all naturalists who have had the opportunity of investigating this question by the aid of a good series of specimens have come to the conclusion that there is but one, and no traces of any extinct allied forms have yet been discovered. [Illustration: FIG. 32.—Platypus or Duck-bill (_Ornithorhynchus anatinus_). From Gould’s _Mammals of Australia_.]