ORDERS, GENERA, AND SPECIES. 37 



united by a membrane; Body fat; Skin tenacious, covered 

 with excellent feathers; Flesh, for the most part, savoury; 

 Food water-plants, fishes, reptiles; Nest chiefly on the ground. 



most part, polygamous. 



98 Diome- > Albatross, 4 



dea. > ' 



99 Alca. Auk, - 13 



100 Uria. Guillemot, 6 



101 Colymbus, Diver. - 9 



103 Sterna. Tern, - 46 



104 Larus. Gull, - 27 



105 Procellaria. Petrel, - 30 



106 Mergus. Merganser, 5 



107 Anas. Duck, 145 



108 Apten- J . 

 odytes. 5 



109 Pelecanus. Pelican, 39 



110 Phaeton. Tropic Bird, 4 



111 Plotus. Darter, - 5 



'uin, - 15 



I 



It may be here useful to the student to observe, that iu 

 the preceding arrangements, the Orders and Genera have 

 but one name for each, respectively; as, for example, 

 AcciPiTRES or tlie Hawks, and Falco or the Falcon genus. 

 Naturalists have, however, found it extremely convenient, 

 in describing the Species of each genus, to give the generic 

 and the specific name together, in order to that correctness 

 of identification, without which our science would be vague. 

 • Thus, to distinguish the Golden Eagle from others of the 

 same genus, but specifically different, it is called Falco 

 Chvysaetos, and so of all the rest of the tribe of Birds. This, 

 at first sight, might seem a cumbrous nomenclature, but, if 

 it bo examined without prejudice, its utility will bo, it is 

 presumcl, apparent. Indeed, in our Common Nomenclature 

 of Birds, wc have adopted, in part, a similar, yet by no 

 means so accurate, a method : thus we have the House 

 Sparrow and Hedge Sparrow, the Woodlark and Titlark, 

 the Water Rail and Land Rail, SiC. Sfc. Some additional 

 observations relative to this subject will be found in the 

 Preface, which see. 



Having adverted to several systcmalic arrangements of 



