Having entered the North Transept, we find the whole of the western end occupied by the colossal Egyptian Figures from Aboo Simbel. We shall view these to the best advantage from the further end of the Transept, in front of the Mammoth Tree; we will, therefore, first make the circuit of the fountain, examining the surrounding objects, and inspect them from that point, and thence commence our return journey down the Nave. The two semicircular extensions at this the upper end of the fountain basin have been separated from the main body of the water by a perforated partition, and contain some curious and interesting animals. In that to the right, or immediately in front of the Assyrian Court, sports one of the most remarkable of the animal creation--the _Lepidosiren_. It is remarkable as being an animal organised with both _lungs_ and _gills_, which are generally assumed to be distinctive organizations in the reptile and the fish; but this, it will be seen, like most of such wonders in natural history, is a conformation of the animal to its habits of subsistence, place of residence, and the exigencies of its life. It is found in the river Gambia, in Western Africa. During a great portion of the year this river is dried up, and the mud in its bed is baked under an ardent tropical sun till it is of immense hardness, and shines when cut with a knife. When the river subsides, and parches up, the Lepidosiren burrows into the mud, where it remains during the dry period, till when the rains come, and the river swells, it issues from the softened mud and sports in the water again. It is considered by the most able naturalists to belong to the reptilia rather than the fish. The exact nature of its food is not accurately known, but it is a voracious feeder on animal substances; this specimen regales himself upon raw beef, frogs, and snails, with the occasional delicacy of a gold fish. He is himself eaten as a delicacy by people in Africa. In the corresponding compartment on the other side of the basin are two species of fresh-water tortoises, _Emys Caspia_ and _Emys Gambiensis_, one an European and one an African species, which may be identified by its larger size and lighter colour. The _Emys Caspia_ is found commonly in the rivers of most of the warmer countries in Europe. When, after the Crimean war, the troops garrisoning the Ionian Islands returned to England, one of the officers brought with him two eggs of this variety; for safety he put them into his pistol-case. On his arrival in England the eggs were found to be hatched, and the two small animals were presented to the Crystal Palace Company, and placed in this basin. One has since died, after living some months; the other is still here.