386 Chandler . — A Study of the Characters which serve to 
surfaces ; on the lower they are irregularly scattered from apex to base, 
but are few in number, or absent, around the margin and along the median 
dorsal angle. On the upper they are very abundant, occurring more or 
less unevenly on either side of the median line, both on the decurrent 
and falcate parts of the leaf, but they are absent from the median 
line itself and from the thick margin (Fig. 1, b). Nevertheless, despite 
the general differentiation into stomata-bearing and non-stomata-bearing 
regions, the limiting line between the two is ill-defined and sinuous. 
Though the general distribution of the stomata can readily be seen, the 
actual details of cell structure can only be distinguished occasionally. Each 
stoma is ringed by about four narrow, parallel-sided cells (Fig. 2, #), and 
usually three or more stomata occur in a row placed end to end, while the 
(a) Cb) CO 
Fig. 1. Distribution of stomata on the upper surface 
of leaves, (a), Sequoia gigantea ; ( b ), S. Couttsiae ; (c), 
Atlirotaxis laxifolia ; j = stomata. Above dotted line 
= falcate part of leaf. Below dotted line = decurrent part 
of leaf, a = attached area. 
Fig. 2. Detail of stomata and non- 
stomata-bearing cuticle. ( a ), . 9 .* gigantea ; 
(b), S. Couttsiae ; (c), A. laxifolia ; s — sto- 
mata. 
cells of the interspaces have curved outlines. In areas where stomata are 
absent the cuticle cells are elongate parallel to the length of the leaf. 
A comparison of the fossil with recent Sequoia and Atlirotaxis shows 
that it is related to the former (compare Fig. i, a, b, c, and Fig. 2, a , b , c), 
for in Atlirotaxis the stomata on the lower surface of the leaf occur only 
where the decurrent base merges into the falcate portion (compare 
description of Sequoia above), while on the upper surface they are confined 
to the falcate region, where they occupy a clear-cut, inverted-V-shaped tract 
shown in Fig. 1, c. There is no alined arrangement ; instead, stomata are 
evenly and thickly scattered over the whole V-shaped area ; the cells 
between them are triangular and are radially arranged (Fig. 2, c ). The 
evidence from the leaves is, then, fairly conclusive that the fossil belongs not 
to Atlirotaxis but to Sequoia . 
