DESCPJPTION OF SPECIES— CnAIiACE^—MUSCl. 43 



described here. This Fucus has been found in a fossil state in the Tertiary 

 formations of Spitzbergen, as recognized by Heer. Another species, Sphcero- 

 coccites crvipiformis, (Sternb.) Schloth., Petref, i, p. 35, pL iv, fig. 1, from 

 the Lignitic Tertiary of Bohemia, is also related to the American species. 

 Habitat. — Point of Rocks, Wyoming Territory (Dr. F. V. Hayden). 



CHAPvACEJS. 



We have to pass over i\\\s- order of plants without mentioning, as refer- 

 able to it, any fossil species from this continent. It is indeed peculiar that 

 remains of tliis kind have not been discovered as yet in our Tertiary measures, 

 for the plants of this genus are quite as frequent in the shallow lakes, the 

 ponds, and the calcareous springs of North America as they are in Europe. 

 The fossil Characece. are mostly known by their seeds, which, though small, could 

 be easily discovered in the soft black shale or clay of the Lignitic measures, 

 where they should be carefully searched for by the collectors of paleonto- 

 logical remains. The seeds vary in size from one-half to two millimeters, 

 and are easily recognized, though small they may be, by their round-oval 

 form, and their surface, upon which the valves are generally marked by dis- 

 tinct spiral lines. Of the thirty-seven species described by European paleon- 

 tologists, eight only are known by their stems and branches; all the others 

 are described from the size of the seeds and the disposition of their spiral 

 lines. Of the whole number, one species only is known from the Wealden 

 or Upper Jurassic; none from the Cretaceous. The other species have been 

 recognized from the different stages of the Tertiary. 



MUSCI. 



One species of Moss only has been discovered in a fossil state in the 

 Lower Lignitic of the West, while more than twenty-five have been described 

 by European paleontologists, all from the Tertiary measures. At the present 

 epoch, most of the Mosses, growing in the water, upon the ground, the rocks, 

 and the trees, are easily decomposed and destroyed, naturally destined as they 

 are to the formation of humus, and, when upon trees, to the absorption 

 of humidity, either as protection to the roots or as a more active agent of 

 decomposition of the wood. Most of the hard, woody species of mosses live 

 upon the peat-bogs and enter into their composition for the production of the 

 combustible matter. Their discovery in this case is out of question, for 



