186 Observations on the 



can be represented. Many of the Linnean genera, it is to be 

 recollected, are limited to a single species; many contain but two 

 or three ; and some do not extend beyond ten or twenty. It 

 consequently follows, that a considerable number will embrace 

 more than the average proportion, and that some will extend 

 even to hundreds. A single example will illustrate this point ; 

 and I shall select the Linnean genus Falco as an instance, not so 

 much because it is the most copious in species, for in this respect 

 it falls far short of many others, but because it is one where the 

 enemies to what is called innovation take up their strongest posi- 

 tion. The number of species contained in this group, which, 

 in the days of Linnaeus, it may be remembered, did not ex- 

 ceed thirty-two, amounts, in the last edition of Dr. Latham's 

 u Synopsis," to two hundred and forty-seven.* Now let us sup- 

 pose that a student has a specimen of a bird before him, which 1 

 he has ascertained to appertain to the Falco of Linnaeus, and 

 whose name, and particularly whose place in nature he wishes to 

 discover, it follows, that he must compare his bird with the de- 

 scriptions of two hundred and forty-seven congenerick species, 

 before he can be satisfied with accuracy respecting its proper 

 denomination. I here state no imaginary or fictitious case. It is 

 one of every-day occurrence. 



Now let us suppose, on the other hand, that, according to 

 modern views, the great genus of Linnaeus, or what perhaps more 

 properly may be termed his family, is divided into five primary 

 departments, distinctly characterized, and that these are again 

 subdivided into five groups equally defined in character, which 

 contain under them, at the highest estimate, we will say twenty 

 species. — I speak here of course only for the sake of illustration ; 

 these proportions must considerably vary. — In this case, then, the 

 student has to compare his bird, in the first instance, with the 



* 1 content myself with the number actually admitted into our best standard 

 Work on Ornithology. I could encrease this number to considerably more 

 than three hundred, were I to include the species daily described, and -which 

 have become known to us since the publication of that part of Dr. Latham's 

 work which comprises the Falcons. The number in the text is quite sufficient 

 of itself to answer the purpose of my reasoning. 



