S42 Mr. Vigors's Sketches in Ornithologi/. 



table which may at first sight be considered doubtful as to the im- 

 portance of their distinguishing characters, I feel myself perfectly 

 justified in the reflexion that they have been established by natu- 

 ralists of the highest authority in tlie science, upon whose general 

 acumen and accuracy it is almost superfluous for me to affirm that I 

 have every inclination to rely. 



But though there may be some difi"erence of opinion respecting 

 the sufficiency of those apparently minour peculiarities for forming 

 the groundwork of generick distinction, there can be no hesitation, 

 I should presume, in admitting the validity of those stronger cha- 

 racters which distinguish the more prominent groups. In general, 

 perhaps, those points of distinction may be considered of doubtful 

 validity, which are novel, or not hitherto employed for the pur- 

 pose of separation : but we may venture, I fancy, to take it for 

 granted, that a character which has at all times, and by all per- 

 sons, been actually employed in drawing a line of demarcation 

 between great and leading groups in Ornithology, is of a nature 

 sufficiently explicit and prominent to be again employed for a 

 similar purpose. If therefore we can adduce an instance in which 

 such a decided and generally admitted mark of distinction exists 

 in the groups of which I have just treated, it appears to me that 

 the separation of them by such a character may be allowed even 

 by those who are the least willing to concede the point. It may 

 be observed then, that, in the great series of genera into which 

 Linnseus has disposed the Class of Birds, the character of a notch 

 in the upper mandible is employed as a prominent ground of dis- 

 tinction. His genera Muscicapa, Lanius^ Tardus, and others, are 

 at once characterized by this leading peculiarity. In the forma- 

 tion of groups of even still higher rank, the notched bill is still 

 admitted as a decisive mark of separation ; and the " Dentirostres" 

 of M. Cuvier, the " Insectivores" of M. Temminck, and cor- 

 responding groups of other naturalists are founded on this strong 

 character alone. The reason is evident. The apparent dentation 

 of the bill formed by this notch is indicative of the raptorial 

 habits of the bird and its animal food. It is this character wiiich 

 exhibits the analogical relation that exists between the Insect- 

 ivorous Tribe of the Insessores and the true Birds of Prej/. And 



