BY^ PROFESSOR STEPHENS. 355 



It was in all probability a period of great replacement in the 

 marine fauna also, no record of which, however, is preserved, 

 except in the New Zealand formations ; and these, though corres- 

 ponding more or less, do not at present allow of a precise corre- 

 lation. There is no positive evidence on this side of any sub- 

 mergence, though it has been strongly suspected on other grounds, 

 and is suggested by the complete and final disappearance of the 

 Glossopteris flora from New South Wales, taken together with its 

 subsequent development elsewhere. The severity of some portion 

 of this period is indicated by the Glacial conglomerates of Bacchus 

 Marsh in Victoria, which can not reasonably be referred to any 

 other epoch, and by the similar and probably contemporary 

 characteristics of th^ Ecca conglomerates in South Africa. The 

 Burrum Coal Measures of Queensland, and perhaps also the 

 Estheria shales and even the Ballimore beds in New South Wales 

 may possibly indicate intervals of more favourable climatic con- 

 ditions, such as are testified to by unequivocal evidence during 

 the great Glacial age of the north. 



It is impossible at present to do more than guess at the 

 (geological) length of this period, during some part of which I 

 take the Bacchus Marsh conglomerates to have been formed. 

 At its conclusion, however, and after these regions had settled 

 dow^n again under a condition of things not unlike that which 

 had preceded, we find a different flora, quite new to this 

 country, occupying the same ground (more or less) as the 

 lost Glossopteris. This, which I call the Tceniopteris flora, is 

 unanimously declared to be, from the northern standpoint, 

 Jurassic. (If it is derived from the north it is later, and 

 if from the south, earlier than its nominal era.) It is at any 

 rate undoubtedly Mesozoic. The lowest and the uppermost 

 formations of this period, taken as a whole, seem to indicate 

 emergence or elevation of the land, so that its abundant rivers 

 swept out in rapid descent to the ocean, bearing with them their 

 loads of coarse detritus, and depositing only in flood-time their 

 lighter silt and finer sand upon the surface of the plains through 

 which they ran. 



