60 ROYAL SOCIETY OF CANADA 
exhibits this feature, but that it does not necessarily indicate generic 
divergence is fully established by the parallel case to be met with among 
the higher Coniferæ in Abies balsamea.! In the parenchyma cells, the 
upper, lower and terminal walls are thin and not pitted, while the latter 
are also generally curved as in the Cupressineæ and in Araucaria. The 
lateral walls are always furnished with bordered pits which are dis- 
tinguished from those of the adjacent or underlying wood tracheid by 
their smaller size and somewhat different details of structure, as well as 
by their peculiar relation to the ray element itself. These pits are 
found to differ very materially as between, one species and another, with 
respect to their detailed structure, disposition in the cell and number 
within the limits of a wood tracheid. That too much dependence can- 
not be placed upon the stability of these elements of structure as diag- 
nostic characters, is shown in the case of the hard pines, in which 
croup. they are utterly worthless; but on the other hand they are of 
very definite value in the soft pines and other genera of the Abietineæ 
as also in the Cupressinee.? It is therefore reasonable to regard them 
as of possible importance in the present case. 
The structure of the bark has received very little consideration in 
published descriptions. Two species in the present list —C. Brand- 
lingii and C. hamiltonense—embrace a thick bark which is well pre- 
served, and in the latter the structural details are so well defined that 
they will be discussed under the species. 
CorpaITESs, Unger. 
Bib. :—Dana, Man. of Geol., 1875, 349, 371; Nicholson, Man. of Pal., 1879, II. 
436, 437, 446, 448, 461, 462 ; Lesquereux, 2d. Geol. Surv. of Pa., 1880, 
419, 543; and 1884, 419, 543; Unger, Gen. et Spec. Pl. Foss., Vienna, 
1850, 378-381; Lacoe, Cat. of the Pal. Foss. Pl. of N. A., 1884; Dawson, 
Q. Jn’l Geol. Soc., 1883, 460; Carruthers, Geol. Mag., V., 1868, 8 ; 
Williamson, M. Mic. Jn’l, 1869, 66; Lesquereux, U. S. Geol. Surv., 1876, 
1-16 ; Lesquereux, Proc. Am. Phil. Soc., 1878, 324; Dawson, Q. Jn’l 
Geol. Soc., 1874, 215; Williamson, Mem. Manch. Lit. & Phil. Soc. 
X., 1885-1886, 190; Renault, Cours de Bot. Foss., 1881, Pls. 12 & 13; 
Brongniart, Tab. des Gen. de Veg. Foss., 1849, 76, 97; Zittell, Schim- 
per & Schenk, Handb. der Pal., 1890, 865, 870; Knowlton, Am. Geol., 
III., 1889, 106; Knowlton, U. S. Geol. Surv., 1889, 30, 50; Grand ’Eury, 
Geol. et Pal. du Bass. Houil. du Gard, 1890, 316; Schimper, Pal. Veg., 
1869, II., 380; Dawson, Geol. Surv. Can., 1882, 124-125: Dawson, Geol. 

1 Penhallow, Taxaceae and Coniferae, Trans. R. Soc., Can., 1896, II., iv. 50. 
2 Trans. R. Soc. Can., 1896, IL., iv., 33-54. 

