FLORA OF TIIK DEVONIAN. 'II 



changed into films of shining graphite. I have since obtained from 



Mr Hartt a specimen found at Carlton, which, though the indi\ idinl 

 leaflets are more indistinct, shows their general arrangemeni in whorls 

 of eight or nine on a slender Stem, It is a beautiful symmetrical little 

 plant, quite distinct from any of the species in the Coal measures. 



Pinnularia dispalans, Dn. (Fig. 194, L). Smooth slender Bteme, 

 producing nearly at right angles long hranchlets, some of which 

 produce secondary hranchlets in a pinnate manner. Stem and 

 branches having a slender vascular axis. This plant was not very 

 dissimilar from some common forms of Carboniferous PinnularuB. Its 

 main stem must once have been cylindrical, and had a delicate central 

 axis, now marked by a darker line of graphite in the flattened speci- 

 mens. The branches were not given off in one plane, and also show 

 traces of an axis. There are indications that the stems grew in 

 bundles or groups. It was probably, as has usually been supposed in 

 the case of the species in the Coal formation, an aquatic root or sub- 

 merged stem of an Asterophyllites or some similar plant. 



(Lycopodiacece.) 



Lepidodendron Gaspianum, Dn. (Fig. 189, A). Dawson, Quart. 

 Journ. Geol. Soc, vol. xv. p. 483, figs. 3 a-3 d. This species, 

 originally discovered in Gaspe, and described in my paper on the 

 plants of that locality, was afterwards recognised among the fossils 

 from Perry, and more recently at St John ; and numerous and beautiful 

 specimens are contained in Professor Hall's collections from New York 

 State, where the species occur in the base of the Catskill group and 

 in the upper part of the Hamilton group. The varied aspects of the 

 species presented in the numerous specimens thus submitted to me, 

 would, with a less perfect suite of examples, afford grounds for specific 

 or even generic distinctions. Flattened specimens, covered with bark, 

 present contiguous, elliptical, slightly elevated areoles, with an indis- 

 tinct vertical line and a small central vascular scar (Fig. 189). De- 

 corticated specimens, slightly compressed, show elliptical depressed 

 areoles, not contiguous, and with only traces of the vascular scars 

 In more slender branches the areoles arc often elevated at one end 

 in the manner of a Knorria (Fig. 189); and in some specimens 

 the areoles are indistinct, and the vascular scars appear as circular 

 spots, giving the appearance presented by the plants named Cyclostigma 

 by Haughton. All these forms are, however, merely different 

 states of preservation of the same species. This plant is closely allied 

 to L. nothum, linger, but differs in its habit of growth and in the sizo 

 of the areoles relatively to that of the branches. The branches wero 



