104 THR MEDALS OF CREATION. Cuap. VI. 
table substances were ever imbedded in them, could not 
detect a single instance in which the 
apparent mosses, confervee, or alge, 
| were organic; in every case the 
mineral origin of the pseudo-vegeta- 
tion was, in his opinion, unequivocal. 
Some of the beautiful green arbores- 
cent bodies in quartz pebbles, even 
under the microscope, present so 
close a resemblance to confervee and 
mosses, that it is difficult to persuade 
oneself they are not vegetable struc- 
tures; but the observations of M. 
Brongniart appear to me conclusive 
as to their mineral nature.* With 
the exception of three or four species 
of Jungermannia, and four or five 
of Muscites in Amber, M. Brongniart 
states that he knows but one true 
ee fossil plant of the family of Mosses ; 
Moss anv Conrerva, in the Muscites Tournali from thefresh- 
transparent quartz. x 3, ; : : 
water tertiary deposits of Armissan. 
VascuLar, oR AcROGENOUS CryproGamMiA.—These plants, 
as the name implies, possess a more complicated structure 
than the preceding, having vascular tissue as varied as in 
the phanerogamia. ; 
EQuIsETACEZ.—The common species of Equisetum, or 
Marestail, is a plant that grows in marshy tracts, and on 
the banks of ditches and rivers; it has a jointed stalk, 
garnished with elegant sheaths which embrace the stem, and 
verticillate linear leaves: it attains a height of two feet, 
and is half an inch in diameter. In the fossil state there 
are many plants allied to the Equisetum, but only a few 
that are generically the same. 
* See Histoire des Végétaux Fossiles, pp. 29—384. 
