HUGE SHARK’S TEETH.--Ray Lankester figures, in his interesting lectures on extinct animals from which we have quoted the above a gigantic shark’s tooth. It is that of the _Carharodon megalodon_, and is three times the length of the tooth of any living shark. Specimens of this fossil tooth of smaller dimensions are common, and one should be found in every museum. They are obtained from the bone bed of the Red Crag at Felixstowe, but were not originally deposited in it. Many of them have fragments of a yet older sandstone adhering to them. Lankester calculates that his shark was 100 feet long. * * * * * THE GREAT FAMILY OF THE CAMELS AND DEER. The Camel, the Camelopard, the Musk-deer and the Deer are all more or less nearly related. They constitute a branch of the great family of Ruminants, and all chew the cud. With the Camel are associated the Bactrian or two-humped Camel, the Alpaca, the Llama and the Vicuna. With the Giraffe we have the Okapi, and several extinct animals. The Musk-deer stands almost alone. Of Deer there are a great many species. It is easy enough to distinguish these various animals the one from the other when seen living in a Zoological Garden or stuffed in a museum. Indeed, at first sight, there might seem to be no great similarity between a Camel, a Giraffe, and a Fallow-deer. To the student of natural history, however, it becomes of great interest to observe the essential peculiarities of each. These may be grouped as those which prove relationship and those which show differences. We will leave aside the very important peculiarities in the stomach, because but few of our readers will have opportunities for examining them, and will confine our attention to the feet, horns, skull and teeth. All have two hoofs or more, and the Camel group have behind their hoofs a pad which covers the sole. None of them have hollow horns, and in none are their weapons of offence--horns, teeth, tusks, &c.--very effective. In all when adult the cutting teeth (incisors) in the upper jaw are absent, and in most the canines are either absent or much modified. The Camel tribe differ from Giraffes in possessing a pad, and in having, when young, incisor teeth in the upper jaw, and fewer lower incisors by two. They have also strong canines in both jaws, no trace of horns, and nothing to be called tusks. The Giraffes have two, three, or even five abortive horns of very peculiar development. They have very long necks, no pads, no tusks. The canine teeth in the lower jaw, which look like incisors, are much specialised in being cleft or notched. The little Musk-deer has no sort of horn; but his upper canine teeth are large and form tusks.