DESCRIPTION OF SPECIES— CRYPTOGAMIA—ALGiE. 41 



successively unfolding upon another as alternate. The substance of the 

 plants seems, from the deep impressions, to have been very thick and carti- 

 laginous or hard, the surface is rugose in the length, or rather deeply wrinkled, 

 as if the laminae had been compressed on both sides ; and the borders, irregu- 

 larly undulately lacerated, are either round or slightly cuspidate or even 

 emarginate at the top. 



Though the relation of this species to the genus Caulerpa is not distinctly 

 marked, its affinity with Delesseria is still less positive. To this last genus 

 it is related only by the outlines of its flat, thick segments, while it is refer- 

 able to Caulerpa by the mode of attachment of its divisions, comparable to that 

 of Caulerpa ericifolia, Ag., and by their form and the thick cartilaginous sub- 

 stance, of the same character as in C. prolifera, Lam., two species of Florida. 



Some fragments of another species, described in Amiual Report, 1872, 

 p. 374, under the name oi Delesseria lingulata, have not been figured, being 

 too incomplete and of a too uncertain relation. They appear sparsely and 

 separately strewn upon the sandstone, like detached fragments of some com- 

 pound fronds, or like the sacs of some Ulvacece, flattened by compression. The 

 more complete of these, two centimeters long, twelve millimeters broad, is 

 rounded at one end, broken at the other, slightly contracted in the middle, 

 and marked in its length by a costa. But for this last character I should 

 have considered these fragments as referable to the former species. 



Habitat. — Raton Mountains, New Mexico, in sandstone ; both forms. 



CHONDRITES, Schp. 



Chondrites snbslinplex, Lesqz. 



Plate I, Fig. 13. 



Chondrites auhsimplex, Lesqx., Annual Report, 1872, p. 373. 



Frond cylindrical, more or less flattened by compression, with rare, dichotomons, long, flesuous 

 branches, mostly of the same size in their whole length. 



This species is found generally flattened, with its expanded, long, flexuous 

 branches, covering large slabs or passing across layers of shaly sandstone. 

 Sometimes the filaments, or fronds, appear simple, linear, like those of Haly- 

 menites lumhricoides, Heer, Urw., p. 244, pi. x, fig. 11, only longer, thicker, and 

 broader, not granulose ; rarely they branch by a simple forking of the main 

 axis, preserving the same size; some of the divisions, however, gradually 

 decrease in size to a round point half as broad as the main stem. The sur- 

 face is irregularly roughened, especially slightly wrinkled across along the 



