The Newts, of which there are three British species, though agreeing generally with the Frogs and Toads in their passage through an aquatic, tadpole stage before attaining their mature form, differ in the fact that they retain through life the compressed tail. In consequence they constitute, with the Salamanders, the order Caudata or Tailed Batrachians. As the structure, development and habits of the three are much alike their story may be told here in general terms, before proceeding to a description of the species separately. The entire animal is enclosed in a soft skin which develops mucuous and sensory apparatus, arranged principally along the sides and the base of the tail. The two pairs of legs are almost of the same length, the hinder pair being slightly the longer. The hands have four fingers and the feet five toes as in the other batrachians. In general form they are like Lizards, and Linnæus classified them as such and was followed by the naturalists of the earlier part of the nineteenth century. During the breeding season the skin of the males develops into a high crest or fin along the middle of the back. There is a similar development above and below the tail. These developments have a triple importance: they are sexual adornments, swimming aids and sensory organs. Usually terrestrial animals, the adults are impelled to seek the water at the pairing season, and in many cases travel long distances in order to reach the stagnant pools that are mostly favoured. There are minute teeth along the jaws and on the palate; but they serve only to retain their living food. The skin serves the same office of respiration as we mentioned in the case of the Frog, and like it they are compelled when on land to force air into their lungs by a constant pumping and swallowing action of the mouth and throat. [Illustration: *Skeleton of Newt.*]