NOTES ON CALAMOPITYS. 213 
structure of the individual strands can be made out it is very eccentrically 
mesarch, with the centrifugal part of the xylem much reduced as compared 
with the centripetal. 
The leaf-trace above referred to lies outside the wood, probably in the 
pericycle, to one side of the fragment of leaf-base (Phot. 18, Text-figure 1). 
It is a large strand, measuring about 4:5 x 2:6 mm. in diameter, the longer 
axis being tangential to the stem. The greater part is composed of secondary 
wood, which is well developed all round the strand, and is thickest on the 
flanks. Very little of the primary xylem at the centre is preserved. A 
similar strand is mentioned in this specimen by Solms-Laubach (1896, p. 74), 
who, however, describes the secondary growth as feeble and limited to the 
outer side, forming an arc. In our case, the secondary wood forms a wide 
zone, and seems to be about equally developed on the outer and inner face of 
the strand (Text-fig. 1). The structure is obviously comparable to that of 
a leaf-trace bundle of C. americana, in the corresponding position (cf. Phot. 10). 
On one side of the strand there is an irregular extension of the wood, seen 
partly in oblique section. I am doubtful as to its nature; it is possible that 
it may represent the other bundle of the trace, the two strands having been 
erushed together; this part of the tissue has a macerated appearance, and is 
less well preserved than the stele and leaf-base. There is another bundle, 
on the opposite side of the fragment of leaf-base, which appears to correspond 
more nearly with Solms-Laubach's description, but the preservation is bad. 
In the cortex or leaf-base itself two complete bundles are preserved, as 
deseribed by Solms-Laubach (p. 75). Each is elongated, approximately in 
the radial plane *, and has three internal protoxylem-groups, the latter lying 
towards that side of the strand which faces its neighbour. There is, of 
course, no secondary thickening at this level. The structure is identical with 
that of the bundle figured by Solms-Laubach from C. Saturni (l.c. Taf. 4. 
fig. 11) and also agrees with that of the bundles in the leaf-base and petiole 
of C. americana (Scott & Jeffrey, 1914 ; Pl. 27. Phots. 4, 5 ; Pl. 36. fig. 9). 
A small part of the Sparganum hypoderma is preserved. The whole 
structure is that of a Kalymma, as Solms-Laubach has shown. From the form 
and arrangement of the bundles it seems evident that the fragment formed 
part of a leaf-base, rather than of the mere cortex of the stem. 
The same probably holds good for the fragment attached to specimen 97, 
which shows essentially the same structure (Phot. 11). Here the bundles 
have from two to four protoxylem-groups ; there appear to be three in the 
one figured (Phot. 17). Two of the bundles are giving off smaller branches, 
with a single protoxylem. 
As regards the structure of the leaf-base, the three species, C. annularis, 
C. Saturni, and C. americana, seem to be practically identical. 
* The fragment is obviously displaced (see Phot. 18). 
