.G/O PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



jMosses, their sporular sac has a very diiferent insertion and origin 

 from that of these plants, hcing ahnost invariably traversed by an in- 

 truded duplieature of itself, called the columella, and being attached 

 to the walls of the sporangium by a delicate confervoid arachnoid 

 tissue, of which these fossils present no traces. 



The apical dehiscence of the inner sac of Folliculites and the 

 lateral dehiscence of that of Carpolithes do not form valid objections 

 to the alliance wdth Musci, though unknown in that Order. The 

 porous and barred cells of Folliculites may be considered analogous 

 to the curious cellular tissue of Sphagnum leaves ; but there is in 

 Mosses no known analogue of the vascular bundle of Carpolithes. 



Upon the whole I think it probable that these bodies may have 

 belonged to a group of plants more nearly allied to Ferns than to any 

 known living Order, if not absolutely belonging to the Filicoid al- 

 liance ; and, considering how little we know of these fossils on the one 

 hand, and, on the other, the very great diversity of form and anatomy 

 in the sporangia of Ferns, it appears to me to be unadvisable to 

 found upon these specimens an independent family. Added to this 

 is the fact, that the recent discoveries in the reproductive organs and 

 mode of germination of the Cryptogamic plants generally have thrown 

 a light upon these families, which tends rather to enlarge our views 

 of their limits than the contrary. 



DESCRIPTION OF PLATE XVII. 

 (All the figures except 1 a are more or less highly magnified.) 



Fig. 1, a. Folliculites minutulus, natural size ; l,b. the same magnified. 



Fig. 2. Magnified view of another specimen. 



Fig. 3. The same, presenting the dehiscing face. 



Fig. 4. Portion of the outer wall of the sporangium. 



Fig. 5. Vertical section of the sporangium, showing the position of the sporular 

 sac. 



Fig. G, Vertical section of another specimen, showing the inner lining mem- 

 brane (a) and the base of the sporular sac (b), the upper part of which 

 has been removed. 



Fig. 7. Portion of the lining membrane, formed of cylindrical turgid cells with 

 often convex bases and conical opaque apices. 



Fig. 8. More highly magnified view of a portion of the same, showing at a 

 the convex base of a cell. 



Fig. 9. Portion of a fragment of a membrane that appeared to line the cavity of 

 another specimen, but which I suspect was originally beneath that 

 figured at 7. 



Figs. 10-13. Various cells with dots, perforations, &c. in their walls, or trans- 

 verse bands, and which appeared to underlie the superficial membrane 

 of the cavity at different parts of the sporangium. 



Fig. 14. The sporular sac ; showing its acuminate apex with the oval opening (a) 

 below it, and above the opening the remains of the membrane that 

 lined the base of the canal at the apex of the sporangium. 



Fig. 15. Very highly magnified view of the apex of the sporular sac, &c. 



Fig. 16, Membrane of the sac. 



Fig. 17. A portion of the same, showing the beaded appearance of the cell-walls. 



Fig. 18. Spherical and oblong sporules ? 



