PROFESSOR OWEN ON THE GENUS DINORNIS. 341 
««The bones were found in one of the large basins which characterize the auriferous 
region, and lie among the mountains in the interior of the island. These basins are of 
ancient Tertiary date and of large size, being always partially filled up with a Tertiary 
deposit that in physical character, and perhaps also in geological age, may be compared 
to the ‘ Molasse’ in Switzerland. This Tertiary deposit has been partially denuded and 
then overspread by the dispersed materials derived from ancient moraines that at a 
later period were thrown down from the neighbouring mountain ridges. A system of 
lakes then occupied these basins, and indeed over a large area of the province still 
continue to occupy them. During the gradual drainage of the lakes that occupied 
these basins, the incoherent materials were shaped into successive terraces that narrowed 
the basins, and, according to the times of their formation, have more or less relation 
to the present water-run of the country. Wide ascending valleys, bounded by lake- 
terraces, were thus formed, and it is in the terraces which were again formed in these 
valleys that the earliest traces of Moa-bones are to be found. 
‘« T have not visited the Manuherikia Valley, where these bones were found, since their 
discovery ; but I enclose a rough section’, showing its contour and contents, which I 
observed nearly two years since on my first arrival in this country. 
“‘ As Moa-bones are to be found, however, in every deposit of more recent date than 
the above, as, for instance, in river-silts and old water-courses, and even in great quan- 
tities lying quite exposed on the surface of the plains, I am therefore unable to indicate 
the precise geological position in the section from which they were extracted. I under- 
stand that they were met with in sinking a shaft on one of the terraces through a bed 
of dry incoherent sand-rock. The plains which I have referred to as existing in the 
interior have a dry arid climate as compared with the rest of New Zealand, so that they 
are clothed only with wing-grass, that grows in tufts, or ‘tussocks’ as they are called. 
The dry climate and the fact that the bones were imbedded in dry sand prevent our 
necessarily inferring, from the well-preserved condition of the skeleton, that it is of 
more recent date than the bones that are usually found; and, moreover, as some parts 
of the skeleton are quite as much decomposed as the generality of the Moa-remains, it 
is more natural to suppose that the preservation of the more perishable parts of the 
remainder of the skeleton has been due to an accidentally favourable position in the soil. 
* As this interesting skeleton will no doubt be fully examined and described, and the 
species determined, by you, when it arrives in England, it is unnecessary for me to 
transmit to you my notes and measurements of the individual parts of the skeleton. I 
will preserve them, however, for future reference should the specimen itself be acci- 
dentally lost or destroyed. 
‘© T remain, dear Sir, 
“Yours very truly, 
« James Hecror, M.D., F.G.S., 
‘* Provincial Geologist, Otago, N. Z. 
1 See figure 1, next page. 
