OF THE CATAMITES OF THE COAL-MEASUEES. 
501 
name of Volkmannia Binneyi , and referred it to Calamites. I have figured and de- 
scribed another very distinct cone, resembling a Volkmannia *, of which the central axis 
affords the clearest proof of a Calamitean origin. Besides this, I have before me a third 
form of cone, discovered by Mr. Butterworth, in which the fruit-bearing organs are 
arranged in verticils, but of which the structure is very different from that of either 
of the other twof. Of the form described by Mr. Binney and Mr. Carruthers 1 have 
made a number of preparations, and have examined a still larger number of specimens. 
Hence I have now in my cabinet three distinct types of verticillate spore-bearing Cryp- 
togamic cones, in which the structure is exquisitely preserved ; but of these three, that 
which I have described in the Manchester Transactions is the only one of which the 
central woody axis exhibits the same organization as the Calamitean stems now de- 
scribed. It does so in the most minute details ; hence I have no doubt respecting 
its Calamitean character ; but the other two differ so widely from it, from each other, and 
from the stems of all known Calamites, that I greatly doubt the propriety of uniting 
them. When stems, however varied in minor details, exhibit so remarkable a conformity 
to a definite type as I have shown to be the case with all the varieties of Calamites, I 
cannot conceive of the central axes of their fruit-bearing organs becoming so widely 
divergent from that type as must have been the case if the fruits described by Mr. Binney 
and Mr. Carruthers belong to the same genus. In the Calamite the medullary axis is 
purely cellular, and its vascular zone is the more external one even in the youngest 
twigs ; but in the fruit in question these conditions are reversed. The vascular tissues 
are all found in the central part of the axis, involving a metamorphosis to which I know 
no parallel amongst living plants. I would speak on this question with the reserve de- 
manded by limited information, but I am at present disposed to believe that the only 
Calamitean fruit of which the internal organization has hitherto been ascertained , is that 
which I have described in the Manchester Transactions. The others, I suspect, belong 
to the wow-Calamitean forms of Annularian plants, whichever they may be. 
We have as yet failed altogether to correlate, with accuracy, the fruits of which we 
know the organization, and those just referred to as found in the Coal-shales, and of 
which we only know the external forms. Much work remains to be done ere we can 
succeed in this part of an inquiry of which we have but touched the threshold. Are 
we under these circumstances in a position to determine the position of Calamites in 
relation to living plants Recognizing the necessity of proceeding with caution, I think 
we are. A further question also presents itself. Are we to recognize two genera of 
Calamitean plants, or are they all to be included in one genus \ I fear my valued friend 
Adolphe Broxgniart will scarcely agree with my reply to this second question, though 
I think that if he had the opportunity of carefully studying the sections in my cabinet 
* “ On a new form of Calamitean strobilus from the Lancashire Coal-measures,” Memoirs of the Literary and 
Philosophical Society of Manchester, 3rd series, vol. iv. 1869-70. 
f This cone is the subject of a memoir by the author, just published by the Manchester Society, “ On the 
Organization of Volkmannia Dawsoni in which the new fruit is referred to either Asterophyllites or Spheno- 
pliyllum. — October 3rd, 1871. 
MDCCCLXXI. 3 Z 
