Mantell on Fossil Remains from Neio Zealand. 35 



in the relative level of the land and water has taken place since 

 those terraces were deposited, and at no very remote period. The 

 present rivers of the country are described as now cutting deeply 

 the beds of volcanic detritus and silt in which the birds' bones are 

 contained ; and the latter are in some places covered by marine and 

 freshwater deposits. The facts adduced appear to me confirma- 

 tive of the opinion advanced by Mr. Colenso (in J 842), that the 

 true situation of the ossiferous deposit is beneath the surface-soil 

 of the fluviatile beds formed by the present rivers. In the more 

 elevated regions the bone-deposit consists of pure volcanic sand 

 and detritus; while in the low districts and along the coasts it is 

 composed of fluviatile mud or silt, which in many places is cov- 

 ered by modern beds of shingle and gravel. 



II. Description of Mr. Walter Mantells Collection. — I will 

 now describe in general terms the most interesting specimens in 

 the collection formed by my son ; the anatomical details, and the 

 important physiological inferences resulting therefrom, will be 

 laid before the Zoological Society by Professor Owen ; to whom, 

 a s a tribute of respect due for his masterly interpretation of the 

 bones previously transmitted from New Zealand, I have offered 

 the examination and description of every object in the series that 

 he may consider worthy his attention. 



The specimens amount to between seven and eight hundred, 

 and belong to birds of various sizes and periods o[ growth ; some 

 evidently of aged individuals, and others of very young animals, 

 in which the epiphyses of the long bones are still distinct from 

 the shaft. They were catalogued by my son as follows : 



Birds' bones. — Crania and mandibles, 19; vertebrae, 250; 

 sterni, portions of, 7; pelves, more or less complete, 30; femora, 

 37; tibiae,- 42 ; fibulae, 35; tarso-metatarsal, 40; phalangeal, 200; 

 ungueal or claw-bones, 30 : ribs, 30 ; egg-shells, fragments, 36 

 specimens. 



Seals.— Jaws with teeth, portions of crania, vertebras, ribs, 

 scapulae, bones of the extremities. 



Terrestrial mammalia. — One femur. 



The specimens received exceeded the number above specified, 

 an d with the exception of a few of the most fragile (and unfor- 

 tunately the most precious, as, for example, the mandibles, pelves, 

 sterni), arrived in an excellent state of preservation. 



The birds' bones, so far as they have been hitherto examined 

 b y Professor Owen, are referable to five genera ; the crania and 

 Mandibles of three of which were previously unknown. 



1. Dinornis. — This name is now restricted by Professor Owen 

 to the birds which possessed a skull and beak essentially differ- 

 e *tt from any form either recent or fossil- Of this genus there is 

 a nearly perfect cranium, with the upper mandible, and portions 



°f two other skulls. The form of the cranium, especially of the 



? 



