"When the hamster has filled his magazines he covers them over, and carefully shuts all the avenues to them with earth: this precaution renders the discovery of these animals very difficult, and the heaps of earth which they throw up before the oblique passage are the only marks to trace their habitations. The most usual method of making them is by digging them out of their holes, which is attended with much trouble, on account of the depth and extent of their burrows. However, a man versed in this business commonly effects his purpose with good success and profit, for in autumn he seldom fails of finding two bushels of good corn in each habitation, and the fur of these animals is valuable. The hamsters bring forth two or three times in a year, and seldom less than five or six. Some years there are great numbers of them to be seen, and in others scarcely any to be met with. They multiply considerably when the seasons are wet, which causes a great scarcity of grain by the immense devastations they make. "The hamster begins to burrow at the age of six weeks or two months; but they never copulate in the first year. "The pole-cat is a great enemy to the hamsters, which he destroys in great numbers, and even takes possession of their holes. "The back of the hamster is commonly brown, and the belly white; there are some, however, of a grey colour, and this difference may proceed from their age; besides these, others are met with entirely black." The hamsters destroy each other like field-mice; two of them being put into the same cage, the female killed the male in the night, and having divided the muscles that held the jaws together, she devoured great part of his viscera. There are great numbers produced in one year, and are so destructive that in some parts of Germany a reward is fixed on their heads. They are indeed so numerous there that their fur is an important article of commerce. All these circumstances, which we have extracted from the Memoir of M. de Waitz, and the observations of M. de Montmirail, appear to be true, and agree with what we have learnt from other quarters on this subject; but it is not so certain, as mentioned in the same Memoir, that these animals are dormant the whole winter, and recover in spring. The hamster, which we kept during the winter of 1762-3, in a chamber without any fire, and where the cold was intense enough to freeze water, did not become torpid, but moved about, and ate as usual; while the dormice which we had alive were benumbed with a much less degree of cold. Therefore the hamster has not any affinity with the marmot or dormice in this respect; and it is very improperly denominated the _Strasburgh marmot_ by some of our naturalists, since it does not sleep like the marmot, and is not to be found in the vicinity of Strasburgh. SUPPLEMENT.