RATS, 277 



viz. the anticipatory order, reaching England before France, and indeed before it had sot out at all. 

 In 1775 it was taken to North America, some time subsequent to the Black Eat, which had already 

 secured a footing there ; it, however, soon encroached on it, and has now nearly exterminated it. 

 Azara, who wrote in 1801-1802, mentions it as found in Brazil ; and it certainl}' was common 

 in Jamaica at the beginning of this century. Whenever it has once gained a footing, its progress 

 has been wonderfully raf)id. It is as common now in California as anywhere else, although it 

 was unknown there prior to the gold fever. Audubou and Bachman, in 1851, spoke of it as not 

 found on the Pacific Coast. 



The Black Rat is a longer known animal, and, if that can be, its origin is involved in still 

 greater obsciu'ity. From time immemorial it has been the " house rat " of the civilized world. 

 It is, however, now fading away before the Brown Rat, and is so nearly exterminated in Britain, 

 that in most places it has become a matter of difficulty to procure a specimen. It still lingers in 

 some of the out-of-the-way places in the thatched roofs of cottages, or at least did so a few years 

 ago. It may not be so now, for it is difficult to predicate what change may have taken place 

 in a very short time, where we have to do with such a very pushing fellow as the Brown Rat. 

 According to Erxleben, the Black Rat was brought to the New World about 1544, that is, 

 just about fifty years after its discovery by Columbus, and it increased so rapidly, and to such an 

 extent, as to have given rise to the supposition already noticed, that it was introduced into the Old 

 World from the New. It is said to have been introduced at an early period into New Zealand 

 by European vessels, and it has now overrun the island, and nearly exterminated a former native 

 species, the only terrestrial mammal yet ascertained to have existed in New Zealand, The Norway 

 Rat had not made its appearance there in 1843, but it is no doubt by this time executing retributive 

 justice upon the Mrs rattus. 



There are one or two facts connected with these Rats, which, although in the present state of 

 our knowledge, we may be unable to draw any conclusions from them, shoidd be kept in view. 

 The reader knows that domestic animals more readily midergo variation than the real fene nattine. 

 A moment's reminiscence of the numerous breeds of Cattle, Sheep, Dogs, Horses, &c., puts that 

 beyond doubt. Is it the same with the semi-domesticated animals ; that is, those which, without 

 his sanction, have constituted themselves in some shape or other parasites or hangers-on about 

 man ? Mr. Waterhouse, speaking of variations in the Rat, thinks that it docs apply to them. The 

 instances which lead him to make the remark, arise out of the species of Rats brought home 

 by Mr. Darwin, from the voyage of the " Beagle," and which were described by Mr. Waterhouse in 

 the "Zoology" of that expedition. In the Galapagos were foimd two Rats; one of the Vesper 

 tj^e, which does not bear upon the point I have now in view. It doubtless dated its origin from the 

 time when the Galapagos were united to the mainland. But there was another, and it was of the Old- 

 world type. It was very like the Black Rat, but did in some respects differ, — its head was rather 

 shorter in proportion, — its tail was longer, and the tarsi smaller. In other respects, and more 

 esjDccially in the character of the fur (which furnishes good means of distinguishing species) " it very 

 closely resembles that species." Nevertheless, being so far distinct, Waterhouse, to preserve 

 recognition o^it, be it species or be it variety, gave it the specific name of Mus jAcom.Ti, it being 

 found in the island called James Island. If a new species, it is one which has been made within a 

 few generations. We can almost specify the date since which it has been made. Being of the 

 Black Rat Idnd it must have been established on the island previous to the supremacy of the 

 Brown Rat, that is, before the latter had become the commoner kind in ships and houses. Darwin 



