6o 
St opes . — The Missing Link in Osmundites . 
Horizon. ‘ Probably Cretaceous.* 
Type (and only specimen). One wedge-shaped piece cut into slides : 
S i, 2, 3, 4 include the main axis, of which no more remains; slides L i, 
2, and 3 cut longitudinally through the leaf-bases, and slides T i to T 12 cut 
transversely through the leaf-bases. Two pieces of the block remain, 
V. 12640 in the British Museum of Natural History, and a small piece 
returned to the National Museum, Melbourne. The slides are shared 
between the British Museum of Natural History (there numbered V. 12641 
a to j) and the National Museum, Melbourne. 
Discussion. 
The group has aroused so much interest and has already been so much 
discussed that it would be easy to enter into a lengthy statement of views 
about this new member. Its obviously interesting place in the Osmundites 
series will be apparent to all who know Kidston and Gwynne-Vaughan’s 
Memoirs. It fits attractively into their theories, as I pointed out at the 
beginning, and its place is rendered all the more interesting from its com- 
paratively late geological age. On a priori grounds, from the main axis it 
would have, probably, been judged to be of Early Mesozoic if not Coal 
Measure age, while the petioles are of Upper Mesozoic and recent type. 
Comparative accounts of the main genera associated with the group have 
already been made by others, so that I will confine myself to drawing 
attention to one plant now of interest which has not so far been much 
considered in comparison with the group, viz. Botrychioxylon paradoxum , 
Scott ( 1912 ). Secondary wood in ferns is rare ; the two plants do not, 
at first sight, much resemble each other, owing to the very much greater 
extent of the secondary wood in Botrychioxylon , but if one imagines the 
secondary wood only partly formed, as can readily be done by shutting 
off the outer zones of it in the Fig. 7, PL XXXVIII, of Scott’s paper, and 
comparing this with the Photo 3, PI. II, a suggestive likeness can be seen 
which is rather more evident on comparing Scott’s drawing, his PI. XLI, 
Fig. 20. This comparison indicates one more link connecting the charac- 
teristics of the early Botryopterideae with primitive features in the 
Osmundaceae. 
The weft of forms representing the Botryopterideae (from some early 
representatives of which the concensus of opinion allows that the Osmunda- 
ceae were derived) shows a various shuffling, permutation, and combination 
of their features. It is interesting that we now have in this new species the 
actual*combination of a solid somewhat stellate protostele ^together with 
secondary wood and an absolutely typical Osmundaceous leaf-base. 
Whatever its geological horizon, its phylogenetic value is, therefore, high, 
and it is still more intriguing if the form really lingered into the Cretaceous 
life of the Antipodes as this fossil makes probable. 
