Swainson's Birds of Western Africa. 329 



equally extensive opportunities for observation, possessing, 

 apparently, the same mental powers for enabling them to 

 draw legitimate inferences from the facts brought before 

 them ; men whose general attainments are in no respect in- 

 ferior to those above mentioned, who can only trace this said 

 quinary principle in the diseased or perverted imaginations 

 of those who uphold it. 



Whether facts have really evolved the theory, or the 

 theory elicited the facts, is quite immaterial, provided it 

 can be shown that the one is consistent with the other. It 

 appears to us somewhat surprising, considering the general 

 bearing of the question in connexion with the advancement 

 of science, that so little should have been done by those who 

 deny that these principles of classification have any found- 

 ation in nature. If some competent naturalist would give 

 a general summary of all that has been urged in support 

 of the quinary system, and all that has been and can be 

 brought to bear against it, limiting the evidence on either 

 side, as much as possible, to matters of fact, many there are 

 who would gladly avail themselves of the information which 

 might thus be afforded ; and, in the present posture of affairs, 

 such a volume would be no insignificant contribution to 

 science. 



As we are upon the subject of classification, in connexion 

 with quinary groups, it may not be out of place to notice a 

 communication published in the last number of the Natu- 

 ralist (certainly the best article that has appeared in that 

 periodical), from the pen of Mr. Thomas Allis, curator of 

 the York Museum, upon the claim which the Columbidae 

 have to rank with the Pavonidae, Tetraonidae, and other 

 families in the order Rasores ; and, as we know that the 

 writer has ample materials to aid him in this enquiry, and 

 having a high opinion of his powers of accurate observation, 

 we consider his remarks especially worthy of notice. After 

 pointing out in detail the wide distinctions in habits and ana- 

 tomical characters between the Columbidae and other families, 

 he observes : — 



" I now come to the points of agreement between the 

 Rasores and the Columbidae. Here I find myself quite at 

 fault, and shall be glad of the friendly assistance of my 

 readers ; for I find a total absence of that kind of resem- 

 blance, either in habit, function, form, or internal structure, 

 which I think ought invariably to accompany the different 

 families of one order. Indeed, the only points of similarity 

 I can discover between them are, that the one is principally, 

 and the other entirely, a vegetable feeder ; and that they each 



Vol. I. — No. 6. n. s. b b 



