66 Mr. Vigors's Sketches in Ornithology. 



But when once she has cleared the narrow windings of these inter- 

 vening passages, and has ascended the typical heights, she seems 

 to have gained, as it were, a table land, where she can expatiate 

 with a wider range, and indulge herself with more excursive 

 freedom. In the slight sketch of the family of Falconidce^ which 

 I drew out in the last volume of this Journal, this singular pro- 

 pensity is strongly exemplified. Among those groups of short' 

 winged Eagles which intervene in affinity between the more 

 typical Eagles and the Hawks, as also among those groups which 

 form the connecting bond between the Hawks and the true 

 Falcons, we may have noticed a considerable number of forms, 

 somewhat abruptly interchanging the respective characters of 

 both the neighbouring groups, among a rather inconsiderable 

 number of species. While on the other hand, when we examine 

 the typical groups both of the Hawks and the genuine Falcons, 

 we are struck by the disproportioned multitude of species whjch 

 exhibit the typical characters of these groups with little deviation, 

 except in those extreme species which partially blend into the 

 conterminous subdivisions. Observing this peculiarity to prevail 

 so generally in the groups which have already come under our 

 observation, we need not be surprised at finding, that, among the 

 numerous additions which are every day accruing to our stock in 

 Zoology, we should have frequent opportunities of again discern- 

 ing a variety of new forms in such osculant and intervening assem- 

 blages ; but forms, chiefly confined to one, or at least to a very 

 limited number of species. 



When we are presented with any subjects of Zoology thus pe- 

 culiarly circumstanced, — or to recapitulate more particularly the 

 case in question, when we have three or four or more species 

 before us, which, taken together, constitute an intermediate pas- 

 sage between leading groups, but which, separately considered, 

 are endowed with forms differing from each other, and partially 

 partaking of the characters of these conterminous leading groups 

 on each side, — it becomes a question whether we should characterize 

 each species as a separate genus, or unite all into one connecting 

 group. The answer to this question depends upon the nature of 

 the characters that mark these foims. If these are striking, 



