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TODUS, 



the pre-eminent type of the whole group, and 

 which, although hut a portion, retains, par excel- 

 lence, the patronymic name. We have frequently 

 called the attention of ornithologists to that peculiar 

 property possessed by groups pre-eminently typical, 

 whether those groups be large or small, of exhibit- 

 ing a greater number of modifications, in the subor- 

 dinate forms, than are to be found in the other 

 divisions of their own circle. Lawrance, our emi- 

 nent physiologist, long ago announced this fact in 

 reference to the Caucasian race of MAN, the most 

 favoured and highly endowed of all that have ever 

 lived. And it might be established beyond doubt, 

 that this fact, first stated as an isolated and discon- 

 nected remark, might be traced throughout the 

 class of animals now before us ; sufficient, at least, 

 to establish it as one of the laws of nature. There 

 are more genera and sub-genera, in other words, 

 mere variations of form, among the order Inses- 

 9ores, or perchers, than in all the other orders put 

 together, and more in the genus Corvus, the type 

 of all birds, than in any other yet ascertained. 

 The sub-genus before us, like the groups just 



