7A EPEMERUEREUR T C TES 
NOTES ON CALAMOPITYS. ` 209 
states (p. 68) that the primary strand of the leaf-trace where it separates 
from the wood has two protoxylem-groups, placed near the ends of the trans- 
verse section ; his fig. 8 (Taf. 4) shows a leaf-trace still in the woody zone 
of the stele and showing two most distinct protoxylem-groups; the 
reparatory strand lies behind, and the whole appearance is remarkably like 
some of our own sections (Phots. 4—6). The distinction is simply that in 
C. americana the division of the trace is completed somewhat earlier in its 
course than in C. Saturni. Inthe latter species, as in ours, the leaf-trace 
had its own secondary wood, where it first became separate, but it is described 
as limited to the outer side (p. 68). 
It need hardly be pointed out that the evidence from the new series of 
sections finally disposes of the suggestion that the outgoing bundles with 
secondary growth might be the steles of branches. A single strand from 
the peripheral ring passes out and divides, exactly in the manner of a leaf- 
trace and in a way perfectly comparable to that already observed in the 
undoubted leaf-traces of Calamopitys Saturni. ' 
II. Tug Genus Calamopitys. 
. A comparative survey of the species which have been included in this 
genus is required, now that our knowledge has been extended by the 
discovery of a new form, Calamopitys americana, while a division of the 
genus has been proposed by Dr. Zalessky, on grounds which demand 
consideration. 
The genus Calamopitys was established by Unger in 1856 on the species 
C. Saturni from Saalfeld in Thuringia. Our knowledge of the true structure 
of the type species is entirely due to Count Sol ime- Lanbi (1896), who added 
a second species, C. annularis, which Unger had described as a Stigmaria. 
These two species have hitherto been regarded as very closely allied, perhaps 
not even truly distinct. I find, however, considerable differences between 
them ; C. annularis very closely approaches the Kentucky species C. ameri- 
cana, while C. Saturni is in some respects more like C. fascicularis, one of 
the two species separated by Zalessky under the name Zristophyton. 
C. annularis appears never to have been figured since the time of Unger, 
who quite misunderstood its structure. I happen to have in my hands 
several sections of this species, as well as two of C. Saturni, all lent to me 
by the late Count Solms-Laubach some years ago, for comparison with 
C. americana. I have taken advantage of this fortunate circumstance to 
re-investigate the structure, so far as my limited material allows—it is not 
likely to be added to in the near future. For C. annularis the available 
sections are fairly adequate, and I have thought it well to give some figures 
of this imperfectly known species as well as one or two EE EET illustrations 
of the more familiar C. Saturni. 
