On a Cone of Calamostachys blnneyana. 
259 
SUMMARY. 
1. A petrified cone closely resembling those previously described 
under the name of Calamostachys blnneyana (Carr.) has 
been found for the first time attached to a leafy shoot. 
The leaves were small linear structures, arranged in whorls, 
and obviously Calamitean. 
2. The structure and arrangement of the leaves and bracts is 
almost identical, but the leaves were not fused at the base 
The bracts appear to be, structurally, ordinary foliage 
leaves modified for protecting the sporangia, but they also 
had assimilatory functions. 
3. Between the whorls of leaves a large number of small, black, 
hair-like structures occur on the stem. 
4. At the base of the cone, below the last whorl of bracts, is a 
ring of tissue which seems to have considerable resemblance 
to the annulus of the cones of the modern Equisctnm. 
5. The cone described is probably identical with the impressions 
known as Paracalamostachys williamsoni, Weiss, and also 
with Calamostachys grandis, Zeiller, the leaves on the 
pedicel being of the Calamocladns grandis type. 
6. Several species of Calamostachys have been found as impressions, 
attached to different Calamite leaves. Possibly the name 
Calamostachys blnneyana applies rather to a type of 
structure than to a species. 
7. This investigation furnishes part of the evidence required to 
finally settle the much discussed question of the affinities 
of Calamostachys blnneyana. It also indicates that the 
bracts of the cone cannot be regarded as sterilised 
sporophyll lobes. 
In conclusion, I should like to express my sincere thanks to 
Mr. Arber for his constant advice and assistance throughout my 
work. 
BIBLIOGRAPHY. 
Binney, B. W. (68). “Observations on the Structure of Fossil Plants.” 
Mem. Palaeont. Soc., 1868. 
Bower, F. O. (08). “The Origin of a Land Flora.” London, 1908. 
Browne, Lady Isabel (09). “ Tbe Phylogeny and Inter-relationships of 
the Pteridophyta.” New Phytologist Reprint, 
Cambridge, 1909. 
Carruthers, W. (67). “ On the Fruit Spike of Catamites." 
Vol. 5, 1867. 
Journal of Botany , 
