suburbs of that city. By an account published at the time, we find that the mammalia which accompanied the musk buffalo were the mammoth and tichorhine rhinoceros, with the horse and ox;[1] but I can find no record of the occurrence of a hippopotamus, nor of Elephas antiquus or Rhinoceros leptorhinus, in the drift of the north of Germany, bordering the Baltic.
On the other hand, in another locality in the same drift of North Germany, Dr. Hensel, of Berlin, detected, near Quedlinburg, the Norwegian Lemming (Myodes Lemmus), and another species of the same family called by Pallas Myodes torquatus (by Hensel, Misothermustorquatus)—a still more arctic quadruped, found by Parry in latitude 82º, and which never strays farther south than the northern borders of the woody region. Professor Beyrich also informs me that the remains of the Rhinoceros tichorhinus were obtained at the same place.[2]
As an example of what may possibly have constituted a more southern fauna in the valley of the Thames, I may allude to the fossil remains found in the fluviatile alluvium of Gray's Thurrock, in Essex, situated on the left bank of the river, twenty-one miles below London. The strata of brick-earth, loam, and gravel exposed to view in artificial excavations in that spot, are precisely such as would be formed by the silting up of an old river channel. Among the mammalia are Elephas antiquus, Rhinoceros leptorhinus (R. megarhinus Christol), Hippopotamus major, species of horse, bear, ox, stag, &c., and, among the accompanying shells, Cyrena fluminalis, which is extremely abundant, instead of being scarce, as at Abbeville. It is associated with Unio littoralis, fig. 22, also in great numbers, and with both valves united. This conspicuous fresh-water mussel is no longer an inhabitant of
