1892. | NEW YORK ACADEMY OF SCIENCES. 141 
Psilophyton Dechenianus with which I am acquainted,” and he 
makes the P. Dechenianus (Gopp.) Carr. include as a synonym the 
P. robustius Dn. 
Weiss, Zeit. Deutschen geol. Gesellschaft, vol. xli, 1889, p. 168, 
stated that he considered the Drepanophycus spinaeformis Gopp. 
(Nov. Act. Acad. Caes. Leop.-Car. Nat. Cur. vol. xxii, Supple- 
ment, 1852, p. 92, pl. xli, fig. 1) as belonging to that part of the 
genus Psilophyton which includes P. princeps. Weiss proposed, 
since it is claimed by Soms-Laubach that P. princeps and P. robus- 
tius are generically distinct, to restrict the genus Psilophyton to P. 
robustius and allied forms, and since Drepanophycus would be a 
misnomer in reference to the systematic position of the fossil, to 
substitute Drepanophytum for P. princeps. Dawson, op. cit., p. 
553, answers the proposition of Weiss, and states that he does not 
consider Drepanophycus as a Psilophyton, but thinks it is possible 
that it may be identical with his Arthrostigma. It is quite safe 
to say that GOppert’s figure of D. spinaeformis bears very little 
resemblance to the Canadian specimens of Psilophyton, with which 
American paleontologists are well acquainted, thanks to the descrip- 
tions and generous distribution of specimens by Sir William Daw- 
son. Finally, as to the question of priority, Dawson (op. cit., p. 
554) shows concisely and correctly that Drepanophytum Weiss 
would date from 1889, and not from 1852, when Drepanophycus was 
described by GOppert. Weiss answers Dawson’s letter (op. cit., 
p. 554) and reaffirms his previous opinion as to the division of 
Psilophyton into Drepanophytum spinaeforme and D. princeps 
and Psilophyton robustius, ete. (op. cit., p. 555). 
Dawson, Nature, vol. 41, April 10, 1890, p. 537, identifies this 
species from the Old Red Sandstone of Perthshire, Scotland. 
Prosser, Am. Geol., vol. vii, 1891, p. 365, reported specimens 
from Kaaterskill Clove, in the eastern Catskills of Greene County, 
New York, from a horizon several hundred feet above what has 
been considered the base of the Catskill; but the writer’s studies in 
eastern New York lead him to consider the lower portion of the 
so-called Catskill in this region as of an age equivalent to the Che- 
mung and Portage of southern and western New York." 
From the above review it will be seen that Pstlophyton princeps 
Dn., when compared with other Devonian species of fossil plants, 
has quite an extended distribution and is most abundant in the 
Lower and Middle Devonian, but also ranges from the Upper 
Silurian to the Upper Devonian of Gaspé, occurs in the Upper 
Devonian of eastern New York (doubtful Catskill), and is reported 
from the sub-Carboniferous (Waverly) of Ohio. 
Celluloxylon primevum genus and species described by Dawson 
1 Oct. 1, 792. See account of Professor Hall’s paper before the Rochester 
meeting of the Geol. Soe of America on the ‘‘ Oneonta Sandstone,’’ in which it 
is stated that the ‘‘ Oneonta sandstone passed eastwardly into the lower Cats- 
kill and westwardly into the Portage.’?’ Am. Geologist, vol. x (September, 
1892), p. 194. 
