REPTILES IN THE TARN AND THE GREEN LANES. 87 



The Natterjack, or " yellow-back," as it is some- 

 times called, is very unlike the common toad in 

 many respects. Its distribution is not so extensive, 

 but where it does occur, it often does so plentifully. 

 The eyes in this species are more projecting, and the 

 line of bright yellow running down the middle of 

 the back, is not only a good means of identification, 

 but shows the origin of its common name. Its 

 chief peculiarity is the rapid manner with which it 

 can run, almost like a mouse. Not less surpris- 

 ing is its climbing powers, for it can surmount 

 anything that comes across its path. When suddenly 

 found, it has a knack of shamming death a 

 trick very common among the lower animals. In 

 some parts of England, the natterjack is distin- 

 guished by the country people from the common 

 species, by the well earned name of the "Walking 

 toad." Dr. Cooke thinks that the name "natter- 

 jack," is derived from the Anglo-Saxon naedre, 

 " nether," or " lower," (in allusion to the creeping 

 habit of reptiles) and " jack," from jager, " one 

 who runs." 



The development of the higher amphibia, among 

 which our frogs and toads rank, furnishes a good 

 illustration of embryology. It is a known fact that 

 the early or embryonic stages of the higher members 

 of the same group of animals is frequently repre- 

 sented by the permanent condition of the lower. 

 This is exemplified among the objects we have been 

 considering, for the transitory stages of a young 



