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. 



" I 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 counti y. 



"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. 



" I remain, dear Sir, 



" Yours very truly, 



" James Hector, M.D., F.G.S., 



" Provincial Geologist, Otago, N. Z. 

 ' See figure 1, next page. 



