Crocodiles, allied to the three forms now characteristic of India, Africa, and America, have been found in the Eocene of our own country, and several species of _Crocodilus_ have occurred in beds of the same age in North America. Lizards are very ancient, many small terrestrial forms occurring in all the Tertiary deposits. A species of the genus _Chamæleo_ is recorded from the Eocene of North America, together with several extinct genera. Snakes were well developed in the Eocene period, where remains of several have been found which must have been from twelve to twenty feet long. An extinct species of true viper has occurred in the Miocene of France, and one of the Pythonidæ in the Miocene brown coal of Germany. Batrachia occur but sparingly in a fossil state in the Tertiary deposits. The most remarkable is the large Salamander (_Andreas_) from the Upper Miocene of Switzerland, which {166}is allied to the _Menopoma_ living in North America. Species of frog (_Rana_), and _Palæophryus_ an extinct genus of toads, have been found in the Miocene deposits of Germany and Switzerland. Fresh water fish are almost unknown in the Tertiary deposits of Europe, although most of the families and some genera of living marine fish are represented from the Eocene downwards. ANTIQUITY OF THE GENERA OF INSECTS. Fossil insects are far too rarely found, to aid us in our determination of difficult questions of geographical distribution; but in discussing these questions it will be important to know, whether we are to look upon the existing generic forms of insects as of great or small antiquity, compared with the higher vertebrates; and to decide this question the materials at our command are ample. The conditions requisite for the preservation of insects in a fossil state are no doubt very local and peculiar; the result being, that it is only at long intervals in the geological record that we meet with remains of insects in a recognisable condition. None appear to have been found in the Pliocene formation; but in the Upper Miocene of Oeninghen in Switzerland, associated with the wonderfully rich fossil flora, are found immense quantities of insects. Prof. Heer examined more than 5,000 specimens belonging to over 800 species, and many have been found in other localities in Switzerland; so that more than 1,300 species of Miocene insects have now been determined. Most of the orders are represented, but the beetles (Coleoptera) are far the most abundant. Almost all belong to existing genera, and the majority of these genera now inhabit Europe, only three or four being exclusively Indian, African, or American.