258 



PALEOZOIC TIME. 



called Psilotum, whence the name Psilopkyton. The species of the 

 Corniferous era thus far described were from one to three feet high. 



Fig. 484 B. n-e. 



Fig. 484 C. 



Figs, a, b, c, d, Psilopkyton princeps ; e Prototaxites Logani(x%)- 



2. Conifers. — The Conifers are species of the earliest known genus 

 of the family Prototaxites ; and portions of two branches are shown, 

 reduced, in Fig. 484 B, e (from Dawson); the larger was 18 inches 

 across. Another was three feet in diameter, indicating that there were 

 forests of these Devonian yews. 



3. Ferns. — Newberry has found the remains of Tree-ferns in the 

 Corniferous of Ohio, showing that these also 

 were among the trees of the forests. A portion 

 of one is represented in Fig. 484 C. 



The projecting parts over the trunk are the 

 bases of the fallen fronds, just such as occur 

 over the exterior of some modern tree-ferns. In 

 the plate on page 322, a modern tree-fern stands 

 to the left of the middle, and the plants below 

 are small ferns. 



Fig. 484 B, a, Psilopkyton princeps ; b, the growing ex- 

 tremity of a branch, incurved or circinnate; c, d, fructifica- 

 tion. Fig. 484 B, e, Prototaxites Lognni, one eighth the 

 natural size. The species of Tree-ferns found in the Ohio lime- 

 Caulopteris antiqua. s t ne are Caulopteris antiqua Newb. (Fig. 484 C), Cmdopteris 



peregrina Newb. (Protqpteris peregrina Dn). 

 Meek has found, in the" Corniferous beds of Ohio, globular particles, about a twentieth 



