1913.] 



Mount Potts Beds, Neiv Zealand. 



347 



McCoy, which, in Australia, is essentially a Jurassic type, though perhaps it 

 may also occur in the Khaetic. 



From this rapid survey of the Mount Potts flora we see that, while its 

 affinities are essentially Rhaetic, a few Jurassic types also occur, and thus the 

 age of the beds may be either Bhuetic or Lower Jurassic. At present we are 

 unable to distinguish clearly between a Rhaatic and a Lower Oolite flora, so 

 this point need not be laboured here. 



There is little doubt that the Mount Potts beds are, geologically, the oldest, 

 plant-bearing series as yet discovered in New Zealand, and as we have 

 seen they are of Klneto-Jurassic age. Palaeozoic sediments with marine 

 invertebrates undoubtedly occur in the islands, but so far there is no 

 evidence of any land floras of older age than the Rhsetic. Not only is 

 Glossoptcris unknown from New Zealand, but no land plants of Palaeozoic age 

 of any description have ever been found there. There is thus no evidence 

 that New Zealand ever formed part of Gondwanaland, and this is a conclusion 

 of great theoretical interest. 



EXPLANATION OF THE PLATES. 



(All the photographs are by Mr. W. Tarns, Cambridge. Nearly all the figures 



are enlarged. 



Plate 7. 



Fig. 1. — Linguifolium Lillieanum, gen. et spec. nova. On the left, an almost entire leaf, 

 the apex being wanting however. On the right Baiera sp., the base of a leaf. 

 Enlarged x f . 



Fig. 2. — Baiera cf. Baiera paucipartita Nath. An almost complete leaf. Enlarged x f . 

 Fig. 3. — Baiera cf. Baiera paucipartita Nath. A median portion of a leaf. Nat. size. 

 Fig. 4. — Linguifolium Lillieanum gen. et spec. nova. Two fragments of leaves, one nearly 

 apical, the other median, showing the nervation clearly. Enlarged Xf. 



Plate 8. 



Fig. 5. — Tmniopteris Daintreei (McCoy) above, and Palissya conferta (Oldh.) below. 

 Enlarged x -|. 



Fig. 6. — Chiropteris lacerata sp. nova. A nearly complete leaf, showing the incised apex. 



Enlarged Xf. 

 Fig. 7. — Thinnfeldia lancifolia (Morris). Nat. size. 



