Prof. Reiuhardt's Remarks on the Genus Balseniceps. 165 



the sutures between them, — a circumstance likewise found in the 

 Hornbills, Toucans, and Parrots. Next must be considered the 

 very extraordinary clumsiness of the zygomatic arch, which, with 

 a length of two inches, is four lines thick and six to seven lines 

 high, thus offering dimensions which it does not obtain, even 

 approximately, in any other bird. Lastly, the proportions of the 

 lachrymal bone are to be observed. This bone is not only brought 

 forward in front of the hinge between the bill and the brain- 

 pan, as is the case, though rarely, in some other birds, but its 

 vertical branch also is throughout its whole length anchylosed 

 with the bill, so that the larger or smaller aperture leading to 

 the nasal cavity, and otherwise found between these parts, en- 

 tirely disappears. In consequence it seems at first sight as if, 

 against all rule, it was the bill itself that forms the boundary 

 to the orbit ; a formation to which at the utmost but a distant 

 analogy can be shown in the Owls, and partly in the Hornbills, 

 inasmuch as with them the lachrymal bone approaches close to 

 the bill, but does not unite with it. 



When the special characters just discussed are set aside, it 

 will not be difficult to demonstrate in the skull of Balceniceps an 

 essential correspondence with Scopus and the Storks generally, 

 and particularly a greater resemblance to them than to Can- 

 croma and the Herons. A pervading difference between the 

 skulls of the Herons and the Storks consists in the cranium 

 proper, or brain-pan, being comparatively much longer in the 

 former than in the latter, whereupon follows a corresponding 

 difference in the length of the zygomatic arch. In other words, 

 the Herons are distinguished by a considerably elongated brain- 

 pan, while in the Storks the brain-pan is comparatively short. 

 This contrast can hardly be overlooked, whatever forms of the 

 groups in question be examined; but it is most conspicuous when 

 two, the heads of which have about the same absolute length, are 

 selected, for instance, the Common Bittern [Botaurus stellaris) 

 and Scopus umbretta. It will then be found that in the former 

 the brain-pan (measured from the moveable supra-maxillary 

 hinge) is nearly half the length of the latter, and not quite one- 

 third that of the cranium, and that the zygomatic arch is pre- 

 cisely twice as long in the former as in the latter. In entire 



