202 



HARDWICKE'S SCIENCE-GOSSI P. 



ON THE FOSSIL PLANT KNOWN AS 

 CAL AMITE. 



IT may be of interest to the readers of Science- 

 Gossip to learn a little relative to the struc- 

 ture of some of the plants that flourished during the 

 coal formation. 



In opening the subject to my readers I shall 

 begin by describing the structure of a plant known 

 to geologists as the Calamite. 



This plant is looked upon by the generality of 

 geologists as a slender-jointed reed-like plant ; the 

 outside of wbich was fluted like the columns of 

 some of the ancient temples, and the specimens 

 shown to us in proof of this are the flattened shaly 

 or rounded sandstone casts of 

 the plant preserved in most of 

 our public museums. So far as 

 the plant having a jointed stem, 

 the idea is correct (and in this 

 feature it resembles the horse- 

 tails of the present day ; some 

 geologists asserting that the 

 two plants are very close rela- 

 tions). My own observations 

 in investigating the structure 

 of the Calamite bear me out in 

 saying that it was not a slender 

 plant with a fluted exterior, 

 but that it possessed a strong 

 woody cylinder, with a bark 

 forming a regular smooth outer 

 surface, and that those speci- 

 mens shown to us in our 

 museums as the form of the 

 Calamite, are but the casts of 

 the inside (not the outside) of 

 the plant. 



Being favourably situated for 

 collecting these fossil plants 

 showing structure, and having 

 been engaged in collecting them 

 for more than seven years, I am 

 now in possession of a great 

 variety of known and unknown forms. I have been 

 particularly fortunate in finding specimens of the 

 Calamite s showing their structure, in some cases as 

 perfect as when living. Being able also to cut and 

 grind down my own specimens, I think I may say 

 that I bave literally dissected the plant we have 

 under notice. 



The sketches are from specimens in my own 

 cabinet, and will illustrate the internal structure of 

 a few of this tribe of plants. Eig. 107 shows a 

 transverse section of a Calamite, with its cortical 

 layer surrounding the cylinder of woody wedges ; 

 the stem seems as perfect as when living; not a cell 

 or vessel is displaced. It will be seen that at the 



point of each woody wedge there is 'a rather large 

 orifice or canal ; this canal is found to traverse the 

 whole length of each wedge between the nodes or 

 joints of the plant. The structure of the tissue 

 immediately around this canal is scalariform, and 

 would seem to point to its cryptogamic relation- 

 ship"; but as you get further into the woody wedge, 

 the structure gets more like that of the Dic- 

 tyoxylons, the vessels being reticulated.* Eig. 108 

 represents a vertical section of the same plant cut 

 through the node, and it will be seen from this 

 sketch that the cellular tissue filling the spaces 

 between the woody wedges, and also filling a por- 

 tion of the axis, does not cross the axis, except at 

 the node (this is a feature to be found in the pre- 

 sent equisetums). This cellular tissue assumes 



Fig. 107. 



different forms in different plants: in some they 

 are nearly circular, in others of a hexagonal form, 

 and in others they are of an oblong form, in some 

 cases stretching from one woody wedge to another, 

 as shown in fig. 111. In a vertical section of the 

 cellular tissue they are seen sometimes very much 

 elongated, not unlike a vessel divided at intervals 

 transversely; sometimes they assume a fusiform 

 character. By referring to fig. 109, being a tan- 

 gental section of the woody cylinder taken at the 



* I have seen Calanrites with nothing: but scalariform 

 yessels forming the woody wedges ; so that the above must 

 have been a higher type of Calamite than the one here 

 referred to. 



