2D2 A COMMENTARY ON NOS. VII. AND VIII. OP " THE NATURALIST." 



the Pratincoles, the Sheathbill, &c. If sucli be admitted, confessedly as a mat- 

 ter of convenience, along with other genera, such an arrangement might, provi- 

 sionally, be adopted as at least possible ; but when the position assigned to 

 them is vaunted as equally satisfactory with those of genera concerning which 

 there is no difference of opinion, it behoves those who pursue the inductive me- 

 thod of investigation to analyze their claims, as Mr. Allis has so ably done 

 those of the Columbidce, to a place among the Rasores. For my part I greatly 

 admire that gentleman's method of procedure, vastly preferring the positive to the 

 imaginative, in matters of this kind ; for it rarely happens that a deviation in 

 any fundamental character, such as those on which Mr. Allis has founded his 

 conclusions, is unaccompanied by equivalent diversities to bear out the distinc- 

 tion. 



To give an example ; and I select it on account of its having been so over- 

 looked. The crania of the Albatross and Petrels, on the one hand, and of the 

 Gulls and Terns on the other, present essential distinctions, such as those to 

 which Mr. Allis has alluded in the case of the Columbidce, and true Rasores ; 

 and to recur to another of the leading characters mentioned by that gentleman, 

 we find that the former lay, in every instance, a single white egg, whereas the 

 latter produce three, which are blotched with black on a coloured ground. Again, 

 the mode of flight, manner of progression on the ground, texture of plumage, and 

 a variety of other particulars, afford corresponding indications, which are surely 

 sufficient, taken collectively, to warrant their separation into two equivalent 

 divisions, of the rank of families. It would, indeed, be vain to endeavour to 

 point out analogous diversities between the Pavonidce and Tetraonidce, which 

 have been admitted as such. They might subsequently be brought together, as 

 a superior division, to be termed Longipennes, after Cuvier, which would be 

 subordinate to the higher group Natatores. The Yagers (Lestris) would apper- 

 tain to the same family as the Gulls, at least they are considerably more allied to 

 these than to the Albatrosses and Petrels ; though, at the same time, as they are 

 considerably less intimately connected with them than the Terns are, it becomes 

 necessary, in order to represent duly the subordinacy of characters, to institute a 

 minor supergeneric division among the Laridce, or what have been termed sub- 

 families, thus separating the Gulls and Terns from the Yagers. The Albatrosses 

 and Petrels being considered as a separate group, equivalent to the entire Laridce. 

 Of course, the next step is into genera and sub-genera, which latter I should 

 like to see specified in the following manner: — Larus-xema minuta, Slerna- 

 anous stolida, Sterna-rhyncops nigra, §c. ; these pertaining to the order and 

 suborder Natatores Longipennes, and family and subfamily Laridce Larince. 



It is only thus, I conceive, by establishing a long series of successively subor- 

 dinate divisions, that any approach to a satisfactory arrangement is at all prac- 



