On the Groups of the Falconidce. 335 



any pretensions to precision ; and at present I shall content my- 

 self with referring only to the general approximation that appears 

 to exist between them. At a future day I hope to be able to say 

 something more decisive. 



For the clearer explanation of the mode in which the foregoing 

 groups appear to be distributed, I shall draw out the following 

 tabular arrangement, which exhibits at one view their leading cha- 

 racters. In this table I particularize those peculiarities only 

 which chiefly serve to distinguish them from each other, without 

 entering into their minuter characters. These indeed are difficult 

 to be laid hold of, while we have so few subjects for examination, 

 and are obliged to rely so much upon the figures and descriptions 

 of others. The characters, it is also to be observed, are those of 

 the most typical of each group. 



Fam. FalconiDvE.* Leach. 



Caput plumosum. Rostrum forte, aduncum, basi cerigerum. 

 Nares laterales, in ceromate positae, plus aut minus rotundatae, 

 apertae. Digiti externi praecipue mediis counexi. Ungues validl, 

 acutissimi, maxime incurvi, retractiles.+ 



* The British species are distinguished in the following table by Italicks. 



+ The retractile power of the nails consists in the capability of elevatins; 

 them at pleasure, (not of withdrawing them entirely within the skin as in some 

 of the analogous Carnivora) by which means they avoid all contact with the 

 ground or other substances which might destroy the sharpness so necessary to 

 them in seizing their prey ; " c'est a dire," says M. Savigny, " pouvant se 

 replier spontanement sur les penultimes phalanges." The analogical charac- 

 ter thus existing between different departments of the animal world has afforded 

 one of those beautiful illustrations, with which an accurate observation of na- 

 ture furnishes, at times, the philosopher, in his delineations of other branches 

 of science. The following adaptation of these external qualities of animals to 

 the powers of the mind is singularly appropriate, and conclusive. ^STTSp yxp 

 01 ociToi Kxi 01 Xeovrts sv ru •nEfnra.r'iiv svsTpt(povsiv tisu ms owyjxs^ tvx (/.'>) 

 riijv ecKf/.w acvTuv kxi rw o^vtvtx KXTtxrpi^ustv, aru to TToXoTr^ay/xov t« 

 (piXoiAxOds ax/x^v rivx x-xt '^ofji.uiJi.x yof/,i<^ovTBS £%£'!<, ^>7 x.xracvccXtsy.uj(jiiv , 

 IxviS' ix'jrx(^0Xvvu(ji.sv ivrois ^upisrois. Plutarch, de Curiosate. Opera, 

 Vol. 8. p. 67. Ed. Reiske. 



