Relation Between Cycadites and Pseudocycas. 335 
stomata of the latter are scattered irregularly over the entire lower 
surface, with the exception of that part which underlies the vein, 
and the epidermal cell walls, though heavily pitted, are quite straight. 
To clear up the relation between Cycadites and Cycas, it occurred 
to the writer that it would be advisable to examine the cuticles of 
the English specimens, and through the kindness of Dr. E. A. Newell 
Arber in lending material from the Sedgwick Museum, this was 
rendered possible. 
There are two species of Cycadites represented in the Sedgwick 
Museum— C. rectangnlaris Brauns and C. Saportce Sew. In the 
former, a Rhsetic species, the presence of a double midrib is very 
marked but unfortunately the condition of preservation is not such 
that it is possible to examine the cuticle. In the latter, an English 
Wealden species, it is noticeable that in the impression of the lower 
surface there are, at places, indications of a double midrib, though 
usually it is unquestionably single—a state of affairs paralleled by 
Nathorst’s Pseudocycas insignis. In Plate III, Fig.6 shows a strip 
of cuticle from one of these specimens. To the left may be seen the 
midrib, the white line down the centre indicating that it is double. 
As in Nathorst’s material, the furrow between the two ridges over- 
lying the veins is often filled with a dark, opaque substance, difficult 
to clear away, which obscures the double nature. All this central 
region is covered with stomata. Fig. 7 illustrates another prepara¬ 
tion at a higher magnification, and the stomata here are very plain. 
This second pinnule, however, has but a single midrib, though it came 
from the same leaf as the first. The tissue immediately to the right 
of the midrib (Fig. 6) represents the remainder of the lower surface, 
the black line slightly to the left of the centre of the photograph, being 
the edge of the leaf. Here the sinuous walls of the epidermal cells, 
and their arrangement in rows are shown to be identical with those 
figured by Nathorst, but an important difference is the presence of 
additional stomata. As noted above, they occur in large numbers 
down the central groove, but there are also a few others scattered 
irregularly to the right and left of the midrib—in Fig. 6, about ten. 
To the right of the central dark line is the upper surface of the leaf. 
In general character it is like the lower, except for the complete 
absence of stomata and the lack of differentiation of the tissue 
overlying the midrib. From this description of Cycadites Saportce, 
it is evident that the resemblance to Pseudocycas is very close, the 
only point of difference being the additional stomata of the lower 
surface in the former species. 
