DEVONIAN PLANTS. 21 



I have uot been able to inspect the original specimens from which the sections 

 were taken, but the text following the above description refers to them as fragments, the 

 largest of which may have been two inches long, an inch wide, and half an inch thick. 

 The statement is also made that they are calcified and, under the microscope, remind one 

 of Prototaxites (Nematophytou) ; " but the cells are of one- third greater diameter than in 

 A Logani, and are destitute of its peculiar markings, and there are no rings of growth 

 or medullary rays. The wood colls are of good length, somewhat tortuous, loosely 

 aggregated and much thickened by ligneous deposit, which appears to be traversed by 

 many narrow, tortuous lines or pores. The whole stem seems to be perfectly homogeneous, 

 and the only other structure observed was a faint and doubtful trace of the existence of 

 parenchymatous cells in some of the spaces between the fibres." 



In a later commimication,' Sir Wm. Dawson says : " I place these plants here, simply 

 because of the resemblance of their tissues to those of Prototaxites (Nematophytou), with 

 which it is possible they may have had some connection, being, i^erhaps, stems or slender 

 roots of similar species of smaller size. No additional specimens have been obtained since 

 the publication of my paper above cited (Jn'l. G-eolog. Soc), which would indicate that 

 specimens of these plants are rare at Graspé, and they have not been found elsewhere. The 

 original specimens were collected by Mr. Bell of the Geological Survey." 



This plant occurs in the Middle Erian of Graspé, and it will be of interest, in connec- 

 tion with what follows, to bear in mind that the Nematophytou Logani, Dn., although found 

 in the same locality, belongs to a lower horizon, viz., the Lower Erian. 



The desirability of a revision of this species was suggested by its strong general re- 

 semblance to Nematophytou, and by the facts developed by the recent examination of the 

 latter. The results obtained by me from the sections in possession of Sir Wm. Dawson, 

 which were submitted to additional grinding, are as follows : — 



In transverse section, the cells are large, thin walled, somewhat remote and tolerably 

 uniform in size. Our measurements show that they average about 35 /< in diameter, 

 varying from 82 /' to oO /'. It Avill thus be seen that they are, on the whole, fully as 

 large as the largest cells of iV. Loganif but they do uot present the same extreme variation 

 in size, nor is there that peculiar grouping of larger and smaller cells which, in the latter 

 plant, gives rise to the appearance of rings in the stem. We do not lay much stress upon 

 this fact, however, since such tracts of larger and smaller cells may have been present in 

 the original plant, though not represented in the small fragments brought to ovir notice. 

 No radial openings are to be found, but in their place there are frequent small and 

 irregular tracts of open structure into which the cells penetrate very much as in Nemato- 

 phytou. The form of the cells is in most cases well preserved ; in other cases they show 

 the effect of compression in their flattened form. Moreover, a transverse section of the 

 stem is uot transverse to all the contained cells, which are, therefore, not wholly parallel. 

 The somewhat wide areas between the cells are largely occupied by a structure which is 

 not easily made out in all cases, but which consists of smaller tubes running diagonally 

 or transversely to the direction of the general structure, and this is what appears to be 

 referred to in the original description above given, as " a faint and doubtful trace of the 

 existence of parenchyma cells in some of the spaces between the fibres." 



» Oeol. Sur. of Can., Fossil Plants, part i. 20. ^ Trans. K. S. C, vi. iv. 39. 



