240 Mr. H. E. Stricldand on the Structure and Affinities 



nera Ujmpa and Irrisor (or as he terms it, Promerops,) have in 

 reahty no near affinity to each other. He argues that birds have 

 in many cases been arranged artificially in consequence of authors 

 being guided solely by the form of the beak without attending to 

 the structure of the other organs, iVfter pointing out the marked 

 differences bet\Yeen the feet of Upvpa and those of Irrisor, he 

 concludes that Upupa has evident afhnities vdtk the larks {Alau- 

 dina), but that its true position is in a special family of the Tc- 

 nuirostres, in conjunction with Upucerthia and some other allied 

 S. American genera. The genus Irrisor, on the contrary, he con- 

 siders to belong to the Cinny7'id(e, or as they are more con-ectly 

 called, Nectariniidcc, to which they have much resemblance in their 

 glossy plumage. 



Now it is undoubtedly true that the most unnatm-al classifi- 

 cations of birds have in many cases residted from the beak being 

 taken as the sole groimd of arrangement, to the exclusion of the 

 other organs. I do not however think that the juxtaposition of 

 Upupa and Irrisor is really an instance of such a vicious arrange- 

 ment, and I hope to show, that notwithstanding the disagreements 

 in then- feet, tail and plumage, these two genera are in reality 

 very closely alhed. 



It will generally be fomid that when several genera of remote 

 affinity have been brought together in consequence of a resem- 

 blance in the form of their beaks, that resemblance is more ap- 

 parent than real, consisting in a general and superficial agree- 

 ment in the form and outline, while the minor details of structure 

 present differences which at once indicate the true affinities of 

 the respective groups. Thus the gcnns Scythropswas till very lately 

 classed by all authors among the toucans, on account of the ge- 

 neral resemblance of the beak, while if the slightest attention had 

 been paid to the position of the nostrils, it would have been seen 

 at once that its true place is among the cuckoos. A similar su- 

 perficial resemblance in the beak has caused Tichodi-oma to be 

 classed wth Certhia instead of with Sitta, Spjermophila with Pyr- 

 rhula instead of with Guiraca, Oredica and Falcunculus among the 

 Laniincn instead of the Parince, and numerous other cases Avhich 

 might be quoted. 



On comparing Upvpa with Irrisor, however, we find a coinci- 

 dence of structure not only in the general forms, but in the mi- 

 nutest details of the structure of their beaks ; and what is of still 

 greater importance, the beaks of these two birds present certain 

 characters which are foimd in no other group of birds with which 

 I am acquainted. 



Upupa and Irrisor both present to us the remarkable combi- 

 nation of a very long beak with a veiy short tongue. The two 

 mandibles are for three-quarters of their length perfectly solid, 

 the sui'faces of contact beins- smooth and flat ; while in all other 



