LAUREXTIAN AND EARLY PALiEOZOIC. 



21 



have been allied to the club-mosses. This seems to bo 



all that we at present know of land-vegetation in the 



Siluro-Cambrian. So far as the remains go, they indicate 



the presence of the 



families of Rhizo- 



carps and of Lyco- 



pods. 



If we ascend 

 into the Uj)per Si- 

 lurian, or Siluri- 

 an proper, the evi- 

 dences of land veg- 

 etation somewhat 

 increase. In 1859 I 

 described., in "The 

 Journal of the Geo- 

 logical Society," of 

 London, a remark- 

 able tree from the 

 Lower Erian of 

 Guspe, under the 

 name Frotoiaxites, 

 but for which I 

 now prefer the 

 name Nematophy- 

 ton. When in Lon- 

 don, in 1870, I obtained permission to exami e cer- 

 tain specimens of spore-cases or seeds from the Upper 

 Ludlow (Silurian) formation of England, and which 

 h'ld been described by Sir Joseph Hooker under the 

 name Pachytheca. In the same slabs with these I 

 found fragments of fossil wood identical with those 

 of the Gaspe plant. Still later I recognised similar 

 fragments associated also with Pachytheca in the Silu- 

 rian of Cape Bon Ami, New Brunswick. Lastly, Dr. 



Hicks has discovered similar wood, and also similar 

 4 



Fio. 1. — Protanntilaria Ilarknesni (Nichol- 

 Bon), a probable Rhizocarp of the Ordo- 

 vician period. 



