Palaeontologie. 267 



gans or anatomical structure, it cannot be said that the presence 

 either of Hepaticae or of true Mosses in the Palaeozoic rocks has 

 yet been demonstrated. 



Passing- lo the Vasctdares, it is pointed out that a large Pro- 

 portion of Palaeozoic plants were spermophytic, and that hence this 

 flora cannot any longer be termed the Age of Cryptogams. The 

 author adopts provisionally the twofold division into Lycopsida and 

 Pteropsida, and arranges the groups as follows: 

 \ Sphenophyllales j ^rticulatae 



T -j ; Equisetales \ 



Lycopsida p^^^tales 



f Lycopodiales 

 i Filicales 

 Pteropsida Pteridospermeae j g ^phyta 



f Gymnospermeae | ^ ^ ■' 



Beginning with the Lycopsida. the genus Stenophyllum and its 

 four types of fructification. including S. fertile, recently discovered, 

 are briefly described and illustrated. The stem is unlike that of any 

 recent group of plants and finds its nearest parallel in the genus 

 Psüotiim. All the known cones are homosporous. The complex 

 cone, Cheirostrohiis, belonging to a separate family, Cheirostrobeae , 

 of the same group Sphenophyllales, is also discussed. The affinities 

 of the Sphenophyllales with the Equisetales are emphasised, and it 

 is pointed out that the Devonian fossil Pseudohornia iirsina (Nat- 

 horst) is probably related to the same group, and that the habit of 

 the unknown stem on which the Cheirostvohus strohüi were borne 

 may have had something in common with that of Pseudobornia. 



' The Equisetales are next described , and attention is called to a 

 stem, alread}^ described by the author, named provisionally Cala- 

 mites pettyclirrensis, from the Lower Carboniferous of Scotland, 

 which is of interest as bridging to some extent the wide gulf which 

 exists between the Calamarian and Sphenophyllaceous type of stem- 

 anatomy. Some new observations by Mr. Hickling on Palaeostachya 

 Vera are also included, and these lead one to suppose that this type 

 of cone is derived b}" a modification of the Calarnostachys type. 



A section is next devoted to the 'Relation of the Equisetales 

 and Sphenophyllales'. It is found that there are anatomical grounds 

 for believing that the numerous leaves of a Calarnite, like those on 

 certain forms of Sphenophyllum, represent the segment of a smaller 

 original number. With regard to the fructifications, the agreement 

 is more striking. Taking all the characters, vegetative and repro- 

 ductiv^e, into account, the affinity of the Equisetales with the wholly 

 Palaeozoic group Sphenophyllales maj?- be regarded as established. 



Turning to the Psilotales, the structure of the recent genera 

 Psilotimi and Tmesipteris is discussed in relation to the Spheno- 

 phyllales. The author concludes that these two genera form a class 

 of their own, the Psilotales, having most in common with the Sphe- 

 nophyllales, though not wholly without the Lycopodiaceous affinities 

 whicii have hitherto been attributed to them. 



The Chief features of the Lycopodiales, the next group, are 

 summarised, and the morphology of Stigmaria is discussed with 

 the conclusion that the best analogy, though a somewhat remote 

 one, appears to be with the rhizophores of Selaginella. The cones, 

 Lepidostrobi, were all almost certainly heterosporous. The new ge- 

 neric name Masocarpon is applied to an undescribed Lycopodiaceous 

 fructification, which has large, sausage-shaped megaspores, imbed- 



