GENERAL REMARKS. 679 



desirable to base them upon the concurrent testimony of as 

 large a variety of organisms as possible, and to remember 

 that they become less and less reliable in proportion as the 

 organisms on which they are founded, depart from the 

 species now living " {Geikie). 



Mr. Jukes-Browne {The Student's Handbook of Historical 

 Geology) tells us that during the Eocene and Miocene 

 periods, Britain was 2,000 or 3,000 feet higher out of the 

 sea than it now is, and that in all probabihty England was 

 connected with Ireland and France ; Scotland, with Scandi- 

 navia and Greenland ; and Greenland, with America. 

 During the Phocene period, " a movement of subsidence 

 took place, by which a part at least of the British area was 

 lowered considerably from the position it occupied in 

 Miocene times. The area of the North Sea was submerged, 

 and the Eastern part of England was also depressed 

 beneath its waves." The great migration of the larger 

 animals which ook place during the Glacial Age, from 

 Europe into Africa, was easily effected, according to 

 Dr. Wallace, by the fact that these two continents were 

 then connected at Gibraltar, at Sicily and Tunis, and at 

 the Isthmus of Suez. " The large number of remains of 

 Elephants and Hippopotami, and of other extinct Mammals, 

 in the caves of Malta and Sicily, bear testimony to the 

 extent of the land-connection here indicated, which could 

 only have been brought about by a considerable lowering 

 of the Mediterranean waters " (Hull). 



In searching through the records of the past, an 

 examination of fossil Hmbs and teeth is particularly 

 interesting ; because we can obtain from it, direct and 

 clearly expressed evidence respecting the capacity of 

 movement and mode of feeding possessed by animals 

 which inhabited the earth many thousands, if not millions, 

 of years ago. To aid those of my readers who are not 

 acquainted with the anatomy of the horse, I have given 

 a brief description of the bones of his limbs on pages 

 36 to 38, and of his teeth on page 49, 



