Lect. VIII.] VOYAGE OF A NATURALIST. 193 



type of the group is the common Grey or Norway Eat ; 

 he is one of the skilfuUest, and most cunning of the 

 group. But the Beaver is the head or chief of the 

 Order, and his praise is in all zoological treatises. He is 

 at the top ; the Gruinea-Pig and his huge relative, the 

 Capybara, are at the bottom. This is in conformity 

 with the well-known fact that in the southern world, 

 new or old, neotropical or palaeotropical, are found the 

 most archaic or lowest forms. 



Thus, in that special territory, the neotropical, we 

 have the Tapir, the Opossum, and the Capybara, and his 

 little, and perhaps still more archaic, relative the Guinea- 

 Pig. This is exactly what I have found with regard to 

 the Bird class : if you want Birds that refuse to fit into 

 well-made zoological systems, that is the place to look 

 for them. I have had my eye upon the Guinea-Pig for 

 many a year, and, working at him from time to time, I 

 have always found something to surprise and stimulate 

 me. The very air of the neotropics must have blown 

 Darwinism into Charles Darwin, when he made that 

 immortal Voyage of a Naturalist; there "nature 

 wantons as in her prime," — ^there she brings forth out of 

 her treasures things new and old. This feeble-minded 

 neotropical Eodent, the Guinea-Pig, is full of old 

 characters, especially in his skeleton and his skull ; 

 and those who study other parts know that he must 

 be made to take the lowest room in his Order. At pre- 

 sent, neither in the existing Metatheria, nor even the 



