378 



This fine species is related by its reticulation and its size to Saloinia Mil- 

 deana, Heer (Bait. Flor., j). 17, PL III, figs. 1 and 2), differing from it 

 by broader, less distinct, square areolte, the absence of a dividing mid- 

 dle nerve, and the narrowing of the base to a very short pedicel. By 

 these two last characters, this species is unlike any of this genus. It is, 

 however, probable that the two leaves representing it were not, when 

 embedded into the clay, in their full state of maturity, one of them being 

 smaller than the other, and its areolation far less distinct. In the young 

 leaves of the living Salvinia. natans, the leaves, before attaining their 

 full development, have the middle nerve scarcely discernible. 



Habitat. — Point of Eocks, William Gleburn. 



3. Selaginella falcata, Lsqx. 



It has been described already-, but merely from small detached branches 

 and branchlets. The specimen of this Lot represents a fragment of a stem 

 ten centimeters long, one centimeter broad, round, but tlattened by com- 

 pression, covered with densely imbricate leaves of the same form and 

 size as those of the branches. This stem proves the relation of the 

 described fragments to the lycopodiaceous family. 



4. Selaginella laciniata, s2). novJ 



Branches dichotomously divided ; divisions two to three centimeters 

 long; leaflets? opposite, distichous, divided from the base in three to 

 five filiform lacinice, some of them forking at the middle, all curving 

 upward or falcate. 



By its mode of vegetation, the form and divisions of the pinnre or 

 branchlets, these small plants are exactly similar to those described from 

 Dr. Hay den's specimens under the name of Selaginella falcata. The 

 difference is in the remarkable laceration or thread-like divisions of the 

 leaflets. The laciniiiB distinct and in relievo upon the stone are like the 

 veinlets of fern-leaves, when, by maceration and decomposition, their 

 epidermis has been destroyed, or like skeletons of leaves. In this case, 

 however, as these thread-like branches are more or less numerous, either 

 simple or forking from the middle, and thus differing in number and 

 mode of divisions for each leaflet, this appearance cannot result from 

 decomposition in water. It is probable that these remains represent a 

 a kind of lycopodiaceous plant, living sometimes partly immersed, and 

 that, as it happens in numerous species of water-plants of this epoch, 

 the immersed leaves become decomposed, and grow into laciuiate divi- 

 sions, while the emerged ones are entire or undivided. This difterence 

 in the leaves is particularly marked in Xasturtium lacustre, Gmy, known 

 to every botanist. I do not know, however, any Lycopodium species 

 showing this kind of variations in leaves. Even L. immdatum has the 

 leaves of the immersed part entire or without divisions. It is therefore 

 uncertain if the specific separation of these fragments is authorizable. 



Habitat. — Point of Eocks, William Cleburn. 



5. Sequoia breyifolia, Heer. 



About one-half of the specimens of this locality have remains of this 

 species; some have very fine large branches, but no cone has been as 

 yet discovered. 



6. WIDDIlINGTO^'IA COilPLANATA, Lsqx. 



The specimens of this species are better than those formerly exam- 

 ined. One has been figured, representing a tripinuately-divided branch ; 

 primary stems long, round flexuous, two millimeters thick, with dis- 

 tant, appressed, oblong, acute leaves; branches in various angles of 

 divergence, and of variable length, either simple or pinnate or bipinnately 

 subdivided ; ultimate divisions obtuse, some slightly club shaped. 



