270 



PALEOZOIC TIME. 



p. 324). The modern Isoetes (referred to the Lycopods by many 

 Botanists) are regarded by the best authorities as the nearest allies of 

 the ancient Sigillarids ; they are from an inch to two feet in height, 

 and have nearly linear leaves, but no trunk ; if they were capable of 

 growing upward, like many other Acrogens, and producing a trunk, 

 the plant with its long leaves would much resemble the Sigillarids. 



2. Ferns. — Forty or more species of Ferns have been described 

 from beds of the Hamilton period, the most of them from those of St. 

 John, New Brunswick. One species, a Neuropteris, is represented in 

 Fig. 528 ; part of a frond of another, a Cyclopteris, in Fig. 529, and a 

 single leaflet in Fig. 530. Large trunks of tree-ferns (peculiar in 

 their very large scars), have been found in the New York and Ohio 

 Hamilton beds. 



3. Equiseta or Horse-tails. — This tribe of plants was represented 

 by plants called Calamites (from calamus, a reedy in allusion to their 



Figs. 531, 532. 



Fig. 531, Calamites Transitionis ; 532, Asterophyllites latifolia. 



reed-like or rush-like aspect, Fig. 531 represents a portion of a stem 

 (in horizontal position) flattened out, Like the modern Equisetum, 

 the stem was jointed (at ab in Fig. 531), and separated easily at the 

 joints, and the surface was finely furrowed. The modern Equiseta 

 have hollow stems. Fig. 532 represents a species of Asterophyllites, — 

 the name signifying star-leaf — a plant of undetermined relations. 



4. Gymnosperms. — These plants belong to the order of Conifers, 

 which includes plants related to the Yew, Pine, Spruce, etc. Les- 

 quereux mentions the occurrence of trunks of Conifers a foot in diam- 

 eter, in the Black shale of the Hamilton ; and others, as large or 

 'arger, are described by Dawson from the New Brunswick beds. 



For the descriptions of American Devonian plants, science is largely indebted to Dr. 

 4. W. Dawson (Quart. J. G. Soc, xv. 483, xviii. 296, xix. 458, xxvii. 270; also his 



