NOTES ON CALAMOPITYS. 217 
Dr. Zalessky gives photographie figures of another section of the same 
specimen (I. c. Pl. 3. figs. 1, 2). ‘This was evidently cut near the one I have, 
for all the bundles can be identified (cf. Phot. 22). Both Dr. Zalessky 
(l.c. p. 25) and Solms-Laubach (l.e. p. 72) mention in this case a single 
bundle embedded in the pith, at a little distance from the secondary wood. 
From the former author's photograph (l. c. fig. 2) it is clear that this 
bundle is the reparatory strand of the leaf-trace. The leaf-trace itself is here 
more embedded in the secondary wood and does not seem to have been 
noticed. Presumably the section photographed by Dr. Zalessky was cut 
just above ours, at a point where the separation of the leaf-trace from the 
reparatory strand was more complete. 
In the section figured in the present paper there is another bundle 
(Phot. 22, x), which appears to be embedded in the pith ; unfortunately the 
secondary wood has been cut away at this point, but about three layers of 
cells remaining on the outer side of the strand are clearly parenchymatous. 
The strand in question is identical with the left-hand one of the two shown 
in Dr. Zalessky’s fig. 2. In his section it appears to be almost in contact 
with the secondary wood. It does not seem to be a reparatory strand, for 
no leaf-trace is visible. 
In the circular form and centrally mesarch structure of most of the xylem- 
strands, as well as in their complete isolation from one another, C. Saturni, 
to judge from this specimen, differs sharply from C. annularis and C. americana. 
There is no reason to doubt that the specimen described is typical of the 
species in these respects, thongh in other sections, which I examined in 1901, 
the exact limits of the xylem-strands were more difficult to trace, owing to 
the nature of the preservation. 
Another probable difference is in the occurrence of medullary tracheides, 
which are a characteristic feature of C. americana and appear to be frequent 
in C. annularis, while there is little or no evidence for their presence in 
C. Saturni. This, if established, would be an important distinctive character, 
but as regards the two Thuringian species the data are inadequate for a 
final decision. One small point remains to be mentioned : in our specimen 
of C. Saturni and in some others the medullary rays are often dilated 
outwards, as noticed by Dr. Zalessky (l. e. p. 26), while this is not the 
case in C. annularis or C. americana. This character is obviously of only 
specific value, at most. 
The question of the course of the leaf-trace has been discussed above 
(p. 208), and the distinction in this respect between C. Saturni and 
C. americana pointed out; the data are wanting for a comparison with 
C. annularis. On the other hand, the structure of the leaf-trace on its 
exit from the secondary wood is very much the same in the last-named 
species and C. americana. 
