142 ME. W. K. PAEKEE ON THE STEUCTUEE AND 



Bromceus, " B." 



In this specimen I have not only to describe a difference of age, but also a distinct 

 species. Drawings made by me twenty years since show in a very strong light the 

 difference between the Emu with a somewhat pointed beak, and with a straight culmen, 

 JD. Novoe Hollandiw, and the Roman-nosed kind, which has been termed [op. cit.) D. irro- 

 ratus. My early observations on the latter kind were made on the skeleton of an adult 

 individual in the Museum of King's College, London ; those upon D. Novcb Hollandice 

 were from a young bird (six weeks old) which I obtained early in the year 1844 from 

 the Aviary of the late Sir Robeet IIeeon *. This young individual I will now describe ; 

 and this description and my figures can be compared with the subject of them in the 

 Museum of the College of Surgeons. Although in full age the bill of JD. irroratus 

 acquires a slightly decurved condition, yet that which I have described is very straight, 

 and the contrast between it and this young D. Novw Hollandice is very marked. Here 

 the more delicate bill reminds one much more of the Tinamou, and even of the Apteryx, 

 than the Eoman-nosed kind, where the face is much more like that of the Goatsucker, 

 and the bill very convex at its setting on, not gently arcuate altogether, as in this 

 species. 



This is a very valuable morphological stage, for there has been but little coalescence, 

 and yet the bones have become closely contiguous ; there are also some new bony pieces ; 

 the diploe also has begun to form freely in the interspace between the outer and inner 

 laminae. The part taken by the basioccipital (Plate XII. fig. 2, h.o.) in the formation 

 of the condyle is well seen, the sides only being formed by the lateral elements : on the 

 whole, this transverse and somewhat dimpled condyle is very reptilian, and so is the 

 whole of the basal bony piece. In the Rhea the oblong basioccipital is very mamma- 

 lian ; but here it is elegantly lozenge-shaped, its sides jutting out so as to form not 

 much more than a right angle, the anterior part of the bone being wedged in between 

 the basitemporals [h.t.). Altogether this bone and the basal parts of the sphenoid form 

 a mysterious combination of the characters of the Lizard and the Guineapig (Cavia 

 aperea), and it is most instructive to see this in a bird which seems like the first rude 

 sketch of the feathered type of Vertebrata. 



The large exoccipitals (Plate XII. figs. 1 & 4, e.o.) are now well formed, and appear 

 larger than they really are, because of the addition in their upper edge (outside) of the 

 large opisthotics (Plate XI. fig. 9, op.) ; the ends of the sutures between these bones are 

 not as yet obliterated. The condyloid foramina, and that for the " vagus " (Plate XII. 

 fig. 2), have a large margin of bone inside them, and are thus removed away from the 

 basioccipital ; the tympanic ala of the exoccipital (Plate XII. fig. 4, e.o.) is thick and 

 clumsy, and is only very gently concave anteriorly, whilst in many typical birds, e. g. 

 "Turdinae," " Emberizinae," " Picinse," "Anatinae," it forms a large part of their A'ery 

 elegant " bulla tympani." ^he large pentagonal superoccipital bone (Plate XI. fig. 4, so.) 

 * These came originally from the late Earl of Dekby's Collection. 



