254 NATATORES. 



with their affinities, and with the station they seem naturally 

 to hold), to remove to families of another order ; as the 

 genus Phaenicopterus (Flamingo) to the family of Ardeadce, 

 and Recurvirostra (Avoset) to that of Scolopaddce, in the 

 order Grallatores ; the feet of these birds betokening more 

 analogy than affinity to those of the true Natatores. The 

 present order, like the preceding one, may be divided into 

 five natural families, which (according to the nomenclature 

 now adopted), are thus entitled, Anatidce, Colymbidce, Alca- 

 dcR, PelecanidcB, and Laridce, each taking its designation 

 from the typical or representative genus. Of these, the Co- 

 lymbidce and Alcadce, possessing in a superior degree the 

 structure and qualities that peculiarly fit them for living on 

 the ocean, and being at the same time deficient in properties 

 possessed by the others, which are not so directly essential 

 to that end, may be considered the typical representatives 

 of the order ; for as the order itself, as Mr VIGORS observes, 

 is aberrant, inasmuch as it deviates from what he calls the 

 more perfect structure* of the conterminous tribes or orders, 

 the normal subdivisions will necessarily consist of such 

 groups as carry this deviation to the greatest extreme, and 

 this, upon investigation, will be found to prevail in the dif- 

 ferent genera of these two families. The other three, which 

 diverge more or less from the true natatorial form, as exhi- 

 bited in the Colymbidce and Alcadce, and approximate to 

 each other, as well as to the families and groups of the pre- 

 ceding orders, form the aberrant divisions. The same cir- 

 cular succession of affinities that prevails throughout the 



* When the words perfect structure are used, they must mean that pecu- 

 liar formation which lies equally removed from the two extremes, con- 

 sidered with respect to systematic arrangement; such, for instance, as 

 the central (or typical) form of any division or family. This distinction 

 seems necessary to be made, lest the term should be liable to misconstruc- 

 tion ; as we know that every creature issued perfect from the hand of 

 its Creator, that is, with such an adaptation of its parts and their func- 

 tions to its peculiar habits as Almighty Wisdom alone could produce, 

 P. S. 



