106 
ON THE FOSSIL PLANTS OF THE COAL-MEASURES. 
! 
Pasje at whicli 
Plate. 
Figure. 
i 
1 
1 
reference is 
made to the 
i 
figure. 
] 
by parenchymatous cells with thinner walls ; e, 
hypodermal layer of longitudinally elongated 
sclerous fibres. X 19. Cabinet number, 1915 . 
96 
15 
18 
Small portion of a tangential section near the surface of 
the outer cortex of a stem like fig. 14 : c, one of 
the lenticular masses of hardened cells like fig. 17, c'. 
X 19. Cabinet number, 1915F. 
97 
15 
19 
Transverse section of a stem of the strobilus. Bow- 
manites {VoJhnannia) Dmvsoni, Will,; a, central 
tracheseal axis ; h, exogenous tracheoeal zone ; c, por¬ 
tion of the middle cortex. X 55. Cabinet number, 
1898 D. 
99 ; 
15 
20 
Inorganic sandstone cast of a single internode of the 
medullary cavity of a small Cahnnite. Nat. size. 
Cabinet number, 114. 
1 
101 i 
15 
21 
Central portion of a transverse section of a young 
1 
' 
1 
Calamite : a, inorganic substance filling the cavity 
of the fistular medulla ; a , remains of the medullary 
parenchyma ; h, h, inner angles of the trachemal 
wedges composing the xylem zone. X 25, Cabinet 
number, 1934. 
i 
101 
15 
22 
Transverse section of a decorticated Calamite, the 
j 
1 
1 
1 
1 
j 
whole of the medullary parenchyma of which has 
been absorbed, leaving the vertically elongated 
inner angles of the vascular wedges, b, b, projecting 
into the fistular cavity left by that absorption ; a. a 
central mass of crystalline infiltrated calcareous 
material occupying the cavity ; a, also a similar 
substance, but deposited in the form of stalagmitic 
layers. This inorganic matter, with its undulating 
[)eripheral outline, represents the common inorganic 
casts of clay or sandstone, from wdiich all the zones 
of wood and cortex have disappeared, their onlj^ 
remains being the thin film of carbon with which 
these “ Calamites ” are usually invested .... 
i 
! 
1 
! 
1 
! 
102 
