Zoological Society, 231 



the metatarse is 1 foot 6 in. in the one and 1 foot 4 in. in the other. 

 I think it more probable, however, that ^pyornis had a shorter than 

 that it had a longer metatarse than the Dinoi'nis yiganteus. 



That its leg-bones were smaller is significantly indicated by the 

 difference of size in the fibulae. 



IHnomis. ^pyomis, 



in. lin. in. lin. 



The longest diameter of the upper end ..211 29 



The shortest diameter of the upper end. ,14 10 



This bone in jiEpyornis shows a flat, full, oval articular facet on its 

 tibial side, of which there is no trace in Dinornis. 



Upon the whole, therefore. Prof. Owen concluded that the jEpy- 

 ornis maxirnus did not surpass in height or size the Dinornis gigan- 

 tens, and that it was more probably a somewhat smaller bird. 



From the obvious differences which M. Geoffroy found on com- 

 paring these fragments with the casts of the metatarsus of the 

 Dinornis giganteus, he has inferred with much probability not only 

 its specific but generic distribution, and has proposed for it the name 

 of ^pg amis maximus"^. This distinction is illustrated not only by 

 the metatarsal bones, but by the eggs themselves. Mr. Walter 

 Mantell, of Wellington, New Zealand, has recorded his observation 

 of an egg of a Dinornis found in the volcanic sand, of the magnitude 

 of which he endeavours to give an idea by stating that his hat would 

 have been but large enough to have served as an egg-cup for it. 



The fragments of the egg of Dinornis or Palajjteryx — of what 

 species, of course, cannot be determined — show, after arriving ap- 

 proximatively at their size by the curve of the fragments, that the 

 shell was not only absolutely thinner, but relatively much thinner 

 than in the Ostrich, and a fortiori than in the JEpyornis. The air- 

 pores, also, have a different form, being linear, not rounded ; and the 

 external surface is smoother. 



In the smoothness and thinness of the shell, the egg of the Dinor- 

 nis resembles that of the Apteryx : in the thickness of the shell and 

 the comparative roughness of its exterior, the egg of the ^pyornis 

 more resembles that of the Ostrich and Cassowary. 



Such colour — a dull greyish yellow, as the originals of the eggs of 

 the jEpyornis now at Paris show — may well have been derived from 

 the recent alluvial soil in which it is stated that they were discovered : 

 the darker stain on one part of the circumference of the larger egg 

 seems to have been due to some accidental circumstance. Most pro- 

 bably they were originally white, like the eggs of the Ostrich, and like 

 the fragments of the eggs of the Dinornis : whether an original green 

 tint, like that of the egg of the Emu and Cassowary, would be wholly 

 discharged by long continuance in the soil, may be a question. 



It is most probable that the entire eggs of the j^pyornis were ex- 

 cluded in the usual fertile state, but had suft'ered such want or inter- 

 ruption of the heat requisite for their incubation as to have become 

 addled. 



* From aiirvs alta, opvis avis. The trivial epithet is hazardous, to say the 

 least, with the results of the comparison with the above recorded. 



