152 Ciiuitniati Society of Natural History. 



Proc, vol. 17, 1877, p. 164, as Psilophytum gracillimum, 

 Lesqx.) 



Locality. — Cincinnati, in bed of Crawfish creek; Kentucky, 

 in bed of Licking river. 



Remarks. — The above species was originally described as a 

 land plant belonging to the genus P.^i/op/iytcvi of Dawson. It 

 is, however, associated with marine organisms, and can 

 scarcely be considered as of any other than animal origin. 

 Walcott notes this fact in his paper on " Fossils of the Utica 

 Slate" (advance paper of Albany Institute Trans., vol. 10, 

 1879, p. 21), where he says: "Their occurrence with algae, 

 graptolites, trilobites and brachiopods in the same layers of 

 shale, in a position indicating their growth /;/ situ, taken with 

 their graptolitic structure, precludes the idea of their being of 

 other than marine origin." The specimens as found at Cin- 

 cinnati are generally greatly broken up, and occur in a soft, 

 blue clay, with stems of crinoids, brachiopoda, etc. The 

 species greatly resembles D. tcnuiraniosiis and D. simplex, 

 Wale, from the Utica slate, and D. gracilis Hall, from the 

 "Quebec " group. A form oi Bidhotrephis {B. gracilis Hall) 

 is also very similar to this, and appears to be distinct from 

 other forms referred to the same species. (See Paleontology 

 of N. York, vols, i and 2, 1847, 1852). 



2. D. TEXUIR.VMOSUS, Walcott, 1879. 



Stipe slender, compressed ; branches bifurcating irregularly, 

 frequently subdividing, terminating in filiform extremities; 

 surface a])parently smooth; celluliferous side with smooth, 

 simple, round pits or depressions along the center of the 

 branches; substance corneous, and probably tubular. (Sep- 

 arate from Trans. Albany Insti., vol. 10, 1879, p. 10). 



Ac>ra///i'.— Cincinnati, Ohio. 



Remarks. — This species was originally described from the 

 Utica slate of New York, but it also occurs in the Cincinnati 

 group. Ulrich gives its horizon as between low water in the 

 Ohio at Cincinnati and 200 feet above A specimen in the 

 collection of the late Mr. IT. P. James shows all the characters 

 of the sjiecies. It is closely related to D. gracillimum and 

 occurs at a])()ul the same hori/on at Cincinnati. 



