PRESIDENTIAL ADDRESS. 567 
from Rockingham Bay. This Family is coming more than ever to the front in 
our comparisons, owing to their similarity in various aspects to the ancient 
Botryopteridee. Though the Ophioglossacee have no secure or consecutive fossil 
history, still they may now be accepted as being very primitive but curiously 
specialised Ferns. Perhaps the most interesting point recently detected in them 
is the suspensor found by Dr. Lyon in Botrychiuwm obliquum, and by Dr. Lang 
in Helminthosiachys. This provides a point for their comparison with the 
similar embryonic condition in Danwa, as demonstrated by Professor Campbell. 
The existence of a filamentous initial stage of the embryo is thus shown for 
three of the most primitive of living Ferns. Its existence in all of the Bryo- 
phytes, and in most of the Lycopods, as well as in the Seed-Plants, is a very 
significant fact. Dr. Lang suggests that ‘the suspensor represents the last trace 
of the filamentous juvenile stage in the development of the plant, and may have 
persisted in the Seed-Plants from their filicineous ancestry.’ Such a possibility 
would fit singularly well with the theory of encapsulation of the sporophyte in 
the venter of the archegonium. 
The representation of the ancient family of the Osmundacee in the Australasian 
Flora is very fine, though limited to five living species, while Osmunda itself 
is absent. It is, however, interesting that the family dates back locally to early 
fossil times. It was upon two specimens of Osmundites from the Jurassic Rocks 
in the Otago district of New Zealand that the- series of remarkable papers on 
‘The Fossil Osmundacee’ by Kidston and Gwynne-Vaughan was initiated. It 
is no exaggeration to say that these papers have done more than any other 
recent researches to promote a true understanding not only of the Osmundacez 
themselves, but of Fern-Anatomy as a whole. They have placed the stelar 
theory in Ferns for the first time upon a basis of comparison, checked by refer- 
ence to stratigraphical sequence. It would be leading us too far for me to 
attempt here to summarise the important results which have sprung from the 
study of those fossils, so generously placed by Mr. Dunlop in the hands of those 
exceptionally able to turn them to account. It must suffice to say that it is now 
possible to trace as a fairly continuous story the steps leading from the proto- 
stelic state to the complex condition of the modern Osmunda. These facts and 
conclusions are to be put in relation with the anatomical data fast accumulating 
from the Ophioglossaceze in the hands of Professor Lang and others. From 
such comparisons a rational explanation of the evolutionary steps leading to the 
complex stelar state in Ferns at large begins to emerge. This is no mere tissue 
of surmises, for the conclusions are based on detailed comparison of types occur- 
ring in lower horizons with those of the present day. 
T must pass over with merely nominal mention your interesting representa- 
tion of the ancient families of Schizeacee, Gleicheniacee, and Hymenophyllacee, 
all of which touch the very foundations of any phyletic system of Ferns. Also 
the magnificent array of Dicksoniee and Cyathee, and of the important genus 
Lindsaya—Ferns which take a rather higher position in point of view of 
descent. But I am bound to devote a few moments to one of your most remark- 
able Ferns, endemic in New Zealand—the monotypic Loxsoma, 
This species has peculiar characters which justify its being regarded system- 
atically as the sole representative of a distinct Tribe. It is also restricted 
geographically to the North Island of New Zealand. These facts at once sug- 
gest that it is an ancient survival, a conclusion with which its solenostelic axis, 
its sorus and sporangium, and its prothallus readily accord. I have lately shown 
that the Leptosporangiate Ferns fall into two distinct Series, those in which the 
origin of the sorus is constantly superficial, and those in which it is as con- 
stantly marginal. Zoxsoma is one of the ‘ Marginales.’ It shares this position 
with the Schizeacee, Thyrsopteridee, Hymenophyllacee, and Dicksoniee, and 
the derivatives Davalliee and Oleandree. Its nearest living relative is probably 
Thyrsopteris, which is again a monotypic species endemic in the Island of Juan 
Fernandez. ‘There is also a probable relation to the genus Loxsomopsis, repre- 
sented by one species from Costa Rica, and a second lately discovered in Bolivia. 
Such a wide and isolated distribution of types, which by their characters are 
certainly archaic, suggests that we see in them the relics of a Filicineous state 
once widely spread, which probably sprang from a Schizeeaceous source, and 
with them represent the forerunners of the whole Marginal Series. If we look 
for further enlightenment from the fossils, it is to the Secondary Rocks that we 
