TJie Older Tertiaries of Maude, etc. 187 



from tlie matrix, and are readily crushed between the fingers. 

 It is then found that the ferruginous coat is very thin, and 

 surrounds an earthy internal part of a light fawn colour, similar to 

 the matrix in which the casts are embedded. We have not seen 

 anything comparable to this method of fossil isation, and are at a 

 loss for an explanation of the processes which have brought it about. 



The older volcanic rock in the district is much decomposed, and 

 towards its upper part is full of amygdules of carbonate of lime, 

 while some lumps of radiating crystals of arragonite, about half- 

 a-pound in weight, were found on the slopes. The soil produced 

 from the decomposition of the liasalt is very fertile, and the 

 valley was formerly noted for its vineyards, which have, however, 

 now entirely disappeared, having been uprooted when phylloxera 

 was prevalent in the district some years ago. 



Below the older basalt in the first section indicated, we find, 

 as shown on the map, another outcrop of limestone, which is very 

 variable in its composition. As a rule, it is arenaceous and 

 earthy, and is in places full of casts while actual fossils are 

 scarce. When they were obtained they were so encrusted with 

 a strongly adhering calcareous coat that while we were gathering 

 them we were rarely able to recognise them specifically, and were 

 consequently quite in the dark as to the equivalence of the beds, 

 especially as one of the commonest forms was a new species of 

 Trigonia. There can however be no doubt, as an examination of 

 the faunal list will show, that the limestone represents the lower 

 portion of the Spring Creek section. As we approach the base of 

 the limestone, fragments of slate and quartz make their appear- 

 ance, and gradually become more abundant, till at length we find 

 the limestone has disappeared, and a conglomerate of well-rounded 

 pebbles has taken its place. In the limestone and conglomerate 

 basalt pebbles are conspicuous by their absence, although we spent 

 some time in a careful search for them. This fact, together with 

 the considerable extent of the outcrop, its evident bedding, and the 

 great change in fauna, precludes the idea of its being a talus. We 

 did not, it is true, see the actual junction of limestone and overlying 

 basalt; but, unhesitatingly, agree with the interpretation of Messrs. 

 Selwyn, Wilkinson and Murray as regards their relationship. 



This section then settles the age of the older volcanic rock. 

 1 1 is eocene. In a paper, read by ourselves, on 9th March of 



n2 



