126 LOWER DEVONIAN PLANT REMAINS 
of the freshwater Lower Devonian a somewhat simpler assem- 
blage of plants is met with and this is even more marked in the 
Downtonian where brackish water held (Lang 1937). The simpli- 
fication of type by the absence of the more definite land plants is 
probably an ecological rather than an evolutionary feature. There 
are, indeed, indications that plants of the Lower Devonian and 
Downtonian will be traced back to the Silurian of the northern 
area. At present, however, there is no demonstration of a Siluro- 
Devonian land flora in the Northern Hemisphere, though it may 
have existed, as is afforded by the Lower Devonian of Lilydale 
and Walhalla and the Lower Ludlow of the Monograptus beds of 
Victoria. 
Говвп, PLANTS FROM SANDSTONE BEDS ON THE WARBURTON- 
Woonp’s POINT ROAD NEAR YANKEE JIM CREEK 
If an adequate knowledge of early vascular plants is to be 
obtained, a large number of outcrops, where plant-remains are 
preserved, must be carefully worked. The discovery by Dr. W. J. 
Harris and Dr. D. E. Thomas of another plant-containing locality 
in the Victorian Siluro-Devonian is, therefore, of interest. These 
plant beds are situated in a roadside quarry on the Warburton- 
Wood’s Point Road about 22 miles from Warburton and adjacent 
to Yankee Jim Creek. In the absence of animal fossils, they 
cannot be palaeontologically dated. Dr. Thomas, however, has 
kindly expressed to me his personal opinion that they are strati- 
graphically higher than the Monograptus beds and are probably 
Lower Devonian. The plant-fragments are preserved as flattened 
incrustations in a dark grey sandstone, the plant tissues being 
represented by a brown mineral substance. The majority are 
small pieces of stems, but a few more connected specimens are 
sufficiently distinctive for classification. The identifiable types 
include Pachytheca and Zosterophyllum. 
1. Pachytheca sp. 
Plate VI, Fig. 22. 
The alga Pachytheca was first recognized in Victoria from two 
specimens obtained at Mount Pleasant, Alexandra. Their identi- 
fication enabled some more doubtful objects, from the Centennial 
Beds, to be associated with them as additional though more 
imperfectly preserved examples of the same organism. 
A single carbonized specimen from the beds near Yankee Jim 
Creek can also be identified as Pachytheca sp. It is shown mag- 
nified three diameters in Plate VI, Fig. 22. The specimen is split 
