134 PETRIFACTIONS AND THEIR TEACHINGS. CHAP. II. 



One fact is especially remarkable, and must have excited 

 the surprise of the thoughtful observer, the contrast pre- 

 sented by the vast accumulations of fossil bones of birds in 

 the swamps, morasses, and pleistocene beds of New Zealand, 

 with the excessive rarity of ornithic remains, not only in the 

 formations of the secondary and ancient tertiary epochs, but 

 also in the most recent alluvial deposits of every other country 

 in the world. 



Sir Charles Lyell has commented on the probable causes 

 of the scarcity of relics of so numerous and important a class 

 of vertebrated animals in a fossil state, and suggested, in 

 explanation of the phenomenon, the peculiar organization of 

 birds ; their powers of flight necessarily rendering them less 

 liable to be imbedded in the deltas of rivers, or in the bed 

 of the ocean, than quadrupeds; whilst the relatively small 

 specific gravity of their bodies, owing to the tubular struc- 

 ture of the bones, and the lightness of their feathery dermal 

 integuments, occasions the carcases of such as die or fall into 

 the water, to float on the surface till they are devoured or 

 decomposed. 



But this argument is scarcely applicable to the colossal 

 brevipennate tribes possessing massive and solid skeletons, 

 as the Dinornis and other extinct Struthionidse, of whose 

 bones the ossiferous deposits of New Zealand in a great 

 measure consist. The anomaly is probably attributable to a 

 very different cause, namely, the peculiar character both of 

 the ancient and modern faunas of that country, in the 

 entire absence of terrestrial mammalia. The stupendous Moas 

 of the earlier ages of those Islands had no indigenous ene- 

 mies or devourers, save the carnivorous tribes of their own 

 class. 



In the fluviatile, littoral, and marine deposits, now in 

 progress in New Zealand, the skeletons of birds are not likely 

 to be imbedded and preserved more frequently than in the 

 secondary, tertiary, and alluvial strata, of other parts of the 

 world. No such accumulations of ornithic remains as the bone- 

 beds of Waingongoro or Waikouaiti can. possibly be formed 

 under existing circumstances ; for since the advent of 

 Europeans, a new element of destruction has been introduced 

 into the Islands of the South Pacific ; and the apterous birds, 

 and those possessing but feeble powers of flight, and the 



