AVES. 



289 



birds according to the researches of Cuvier, 

 the discoverer of this remarkable peculiarity in 

 the anatomy of birds. 



Table of the number of toe phalanges in 



Jiirds. 

 Number of Phalanges in the 



The above table shows what are the toes 

 which are deficient in those birds that do not 

 possess the ordinary number. 



The phalanges are expanded at their extre- 

 mities, especially at the posterior ; the articular 

 surfaces are concave at this end, but divided 

 longitudinally by a narrow convex line, to which 

 a corresponding unequal surface at the anterior 



* This is wanting in the Argus Pheasant ; the 

 Pavo bicalcaratus, on the contrary, has two spurs 

 on each metatarsal bone. 



t In the single genus Ceyx among the Insessores, 

 and Hemipodius among the Rasores, this toe is 

 wanting. In all the rest, with the exception of 

 the Swifts (Cypselus) it is directed backwards. 



\ In the Dentirostral Insessores this toe is united 

 by one or two phalanges to the fourth. 



$ According to Cuvier this toe and the fifth in 

 the Swift ( Cypselus) have only three phalanges like 

 the third. In the Goat-suckers ( Cuprimulyus) and 

 Herons (Ardea) the claw of this toe is provided 

 with dentations similar to a comb on its inner side. 



|| This toe is stated by Cuvier to have only four 

 phalanges in the Goat-suckers, and we have ascer- 

 tained the correctness of the exception, and that 

 it also obtains in the Rhea. This toe is united 

 to the fourth toe as far as the penultimate joint 

 in the Bee-eaters (Merops), the Motmots ( Prio- 

 mtes), the King-fishers (Aleedo), the Todies 

 ( Todus), and the Hornbills ( Buceros ), which form 

 in consequence the family Syiuhtctyli of Cuvier. 

 In the S ansores this toe is turned backwards, 

 and assists the Hallux in opposing the other toes. 

 The Owls have the j.ower of turning back the 

 outer toe at pleasure. 

 VOL. i. 



end of the preceding phalanx is adapted, con- 

 stituting a ginglymoid articulation. The ulti- 

 mate or ungueal phalanges are characterised by 

 their anterior pointed terminations, which cor- 

 respond in form, in some degree, to the nature 

 of the claw. 



132. 



Foot of the Goat-sucker. 



Of the fossil bones of birds. Birds differ 

 from each other in a much less degree than qua- 

 drupeds, less, perhaps, than any other class. 

 The Penguin and the Ostrich have, indeed, 

 but a remote external resemblance with the 

 Eagle or the Swallow, but yet they have never 

 been regarded as other than birds. The Por- 

 pesse and the Whale, on the other hand, al- 

 though their real affinities were pointed out 

 by Aristotle, have been placed by many sub- 

 sequent Zoologists in a very different class 

 from the Lion or the Ape, and in the older 

 systems of Natural History they always ob- 

 tained their position among the true fishes. 



Osteological characters of the same value 

 with those which serve to distinguish the 

 genera, and for the most part the species of 

 Mammalia, are, therefore, with difficulty found 

 in the Class of Birds. Cuvier has declared 

 that the differences in the skeleton of two 

 species of an ornithological genus are some- 

 times wholly inappreciable, and that the oste- 

 ological characters of Genera can rarely be 

 detected in any other part than in the bones 

 of the mandibles, which, do not always con- 

 form in a sufficiently characteristic manner 

 with the modifications of the horny bill. 



The determination of the fossil bones of this 

 class is, therefore, conjectural, or, at least, it 

 wants much of that demonstrative character 

 which the bones of quadrupeds afford. 



The fossil bones of birds described by Cu- 

 vier are considered by him to appertain to a 

 species of Buzzard, Owl, Quail, Woodcock, 

 Ibis, Sea-lark, and Cormorant; and, although 

 not remarkable for their number or for their 

 zoological interest, yet they demonstrate that 

 the species which existed at that remote period, 

 when the Anoplotheriums and other extinct 

 quadrupeds trod the face of the earth, had the 

 same proportion of parts, the same length of 

 wings and legs, the same articulations of the 

 toes, the same form and numerical proportions 

 of the vertebra; in short, that their whole 

 organization was regulated by the same general 



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