422 



I am quite aware that there are many local species, birds as well 

 as insects, some rare, others of frequent occurrence, found in the 

 west of England and not in the east. I have already mentioned 

 three instances in the case of birds. But this may probably be 

 accounted for by such species having found no spots suitable to 

 their habits till after travelling long distances, or to their having 

 first got footing in the country by some other road. 



What has been just said respecting the Faima of this part of 

 England relates only to the Fauna of the present day. But, taking 

 a more extended view of the subject, we may regard that Fauna in 

 connection with what it was in days past, as also in reference to the 

 changes it is likely to undergo hereafter. It has been for modern 

 science to discover and ti-ace out the unbroken law of continuity 

 which not only pervades a.ll physical phenomena, but the whole of 

 the organic world. In working out the Natural History of any 

 district we cannot entirely dissociate living forms from those which 

 have ceased to act their part in nature, and which have disappeared. 

 For we can draw no marked line between them. We see, indeed, 

 a broad distinction between the Fauna of these islands at a remote 

 geological epoch and what it is now ; but by slow continuous 

 change one has passed insensibly into the other. Taken at intervals 

 of one or two generations only, scarce any change is pei'ceptible, 

 though still silently going on. It is like watching the hour hand 

 of a clock which, if observed at intervals only of a few minutes, 

 remains to all appearance unmoved, though, when noted at the end 

 of a whole hour, its advance is njanifest. Let us illustrate this by 

 reference to the British Mammals, and those of the Bath district 

 especially. Mr. Moore tells us* that in the gravel deposits of this 

 district constituting the Mammal drift are found remains of more 

 than one species of elephant or mammoth, the long-haired 

 rhinoceros, the great Bos primigenius, the musk ox (Ovibos 

 moschatux ), the reindeer, the wild boar, and the wild horse. None 

 of these animals are now found living in this countiy, and two, the 

 mammoth and the long-haired rhinoceros, have been long extinct 

 everywhere, though believed to have been contemporaneous with 

 man in the earliest periods of his existence on this earth. The 

 Bos primigenius lived on to historic times. The musk ox and 

 * Proceed, of Bath Field Club, vol. ii., p. 51. 



