122 Bower.— Is Eusporangiate or Leptosporangiate 
found in the earlier rocks does not necessarily prove their 
absence at the periods when those rocks were formed, though 
the fact is worthy of note : for our purpose the prevalence of 
certain forms over others in the earlier formations will com- 
mand greater attention, and we may at once proceed to 
consider how, in this respect, the facts of palaeophytology 
bear upon the present question. 
Recent writers have repeatedly remarked the preponder- 
ance of Ferns of the Eusporangiate type in the primary rocks : 
though very many Fern-remains are represented only by barren 
fronds, where the sporangia have been found they are in the 
overwhelming majority of cases of a character allied to the 
Marattiaceae : it may further be stated that no drawing 
from a microscopic section showing internal details of an un- 
doubted leptosporangiate sporangium from the primary rocks 
has yet been published 1 , and it is from these, rather than from 
mere surface observations of prints, that the most trustworthy 
evidence is to be gathered. Perhaps the best authenticated 
example of a print of a Leptosporangiate Fern from the 
primary rocks is that of Hymenophyllites delicatulus , described 
and figured by Zeille 2 , and referred by him to the Hymeno- 
phyllaceae : here the details of the impression were so well 
preserved that Zeiller was able to recognise and draw the 
oblique annulus, which corresponds very closely with that of 
a modern Filmy Fern. The original specimens of this fossil 
were examined by Graf zu Solms-Laubach, and from them 
he concluded ‘that the fact is correctly stated, and that no 
other interpretation of the figures is possible V The spor- 
angia figured and described by Mr. Carruthers as being found 
in a section of a nodule from the coal must also be con- 
sidered 4 . I have had the opportunity, through the kindness 
1 Renault states that he has specimens of sporangia of Gleicheniaceae and of 
Trichomanes in silicified sections from Grand-Croix, but did not publish them 
because he did not know to what fronds they belonged : Cours de Bot. foss. III. 
p. 218. The case of sporangia from a coal nodule figured and described by 
Mr. Carruthers, Geol. Mag., vol. IX, No. 2, 1872 (Plate II, Fig. 5), will be 
referred to below. 2 Ann. d. Sci. Nat., 6 Serie Botanique, vol. XVI, 1883. 
3 Palaeophytologie, p. 157. 
4 Geol. Mag. vol. IX, No. 2, PI, II, Fig. 5.. 
