COMMON WATER-NETVT. 299 



but if examined by the microscope, is, perhaps, of all 

 other objects that can be selected for that purpose, 

 the most eligible for exhibiting a general view of 

 the circulation ; shewing, in the most distinct and 

 beautiful manner, the rapid current of the blood, 

 the particles of which, in this animal, as well as 

 in the rest of the Amphibia, are of an oval form ; 

 not round, as in the Mammalia. In the greater 

 Water-Newt, on the contrary, this part, being 

 nearly opake, can by no means advantageously 

 exhibit the same phenomenon. The female is 

 almost destitute of the dorsal crest, but the tail is 

 furnished with an approach to it, though far less 

 conspicuous than in the male. The general colour 

 of the male is olive-brown, beautifully and dis- 

 tinctly marked with numerous, round, black 

 spots, dispersed over every part of the animal, 

 but largest and most conspicuous on the sides and 

 tail : the abdomen is orange-coloured, the black 

 spots ofteiV appearing rather less intense on that 

 part than on the back. The female differs very 

 considerably in colour, being generally of a pale 

 yellowish brown, much less distinctly spotted, and 

 from the want of the dorsal crest, might he almost 

 mistaken for a different species by a person incon- 

 versant in the history of the animal. On the top 

 of the head, in both sexes, are three or four lon- 

 gitudinal dusky streaks : the eyes are small and 

 gold-coloured : the fore feet tetradactylous ; the 

 hind pentadactylous ; ail destitute of claws, and 

 in some specimens more or less approaching to a 

 kind of palmated appearance towards the base, as 



