350 ON THE STRUCTURE OF THE FRUIT OF CALAMITES. 
paper on " Fossil Plants," contributed to the c Dictionnaire Universel 
d'Histoire Naturelle' (1849), he says, " We should consider the various 
forms of Volkmannia as only the fructification of different species of 
Asterophyllites. but the specific connection of barren and fertile plants 
cannot be certainly determined ; the examination of numerous speci- 
mens, and especially those united in the same branch and occurring in 
the same bed, will eventually clear this up. Volkmannia polystachya, 
Sternb., seems to belong to Asterop/iyllites dubia, Brongn., or to an 
allied form, perhaps Catamites nodosus, Lindl. and Hutt. If this con- 
nection be real, as I am inclined to believe, we should have a largish 
Calamitoid stem, almost arborescent, branches with leaves of Astero- 
phylUtes, and spikes of Volkmannia belonging to the same plant." 
Believing this to be the true relation these different genera bear to 
each other, it is yet desirable to retain the generic name for the various 
fragments of the plants, until they can be built up into particular 
species. I shall accordingly designate the strobilus described by Lud- 
wig as Volkmannia Ludwigi, and that which forms the subject of the 
present paper as V. Binneyi, after the distinguished geologist who has 
examined so successfully the vegetable treasures of the Lancashire 
Coal-field, and from whom Dr. Hooker, as I have already said, ob- 
tained the specimens which I have examined. 
A. Binneyi is a slender, parallel-sided strobilus, 2 lines in diameter. 
I have seen no specimen exhibiting either extremity. The largest frag- 
ment is 10 lines long, and is composed of 15 leaf-whorls. The axis of 
the strobilus has a bundle of fine scalariform tissue in its centre, form- 
ing about a third of its diameter, and generally appearing free from the 
surrounding cellular tissue (Fig. 3), whicli is composed of somewhat 
elongated cells. At regular intervals the axis irives off whorls of 
o 
© 
appendages, which are alternately foliar and fruit-bearing. The foliar 
whorl consists of twelve leaves, which proceed horizontally from the 
axis until they reach the circumference of the strobilus, where they 
take an ascending direction. The leaves are united together by their 
margins until they reach the outside of the fruit, and form a conti- 
nuous septum, dividing the strobilus into a series of chambers. The 
free exposed apices of the leaves are acuminate. A slender vascular 
bundle enters each leaf from the axis. The cells of the lower or hori- 
zontal portion are large and roundish, those of the upper free portion 
are smaller in diameter but more elongated. Each whorl of leaves 
