Contributions to Bird-Anatomy and Classification. 

 Fig. 3. 



Skull of Furnaritts rufus, showing its achizoriinal character 

 (from P. Z. S. 1877, p. 450, fig. 3). 



Furnarius rufus is represented. Referring to this, he says, 

 " It has been my habit to group all the birds possessing a 

 schizorhinal skull in a single major division . . . but the 

 independent development of an identical disposition in the 

 small division of the Passerine birds above mentioned weakens 

 the importance of the character to a certain extent, although 

 it is not at all necessary to assume that it overthrows its 

 significance. Collateral evidence, from visceral and other 

 details, compels me still to think that those schizorhinal 

 birds which possess the ambiens muscle, or are, in other 

 ■words, homalogonatous, must be retained in one great order, 

 Charadriiformes, until some important structural differences 

 are discovered which necessitate their being otherwise 

 arranged. The schizorhinal disposition is most certainly 

 one which is a secondary development upon the normal 

 holorhinal one ; and that it has been independently arrived 

 at in two non-related orders of the class is proof that it 

 results from most simple causes, because the probability that 

 the same complex conformation should appear, de novo, 

 varies inversely as the complexity; the greater the elabo- 

 rateness the less the chance that it, in all its detail, comes 

 into existence more than once/'' 



