CARBONIFEROUS. 23 



writers have stated their belief in the former opinion. This subject I would 

 willingly have left alone, nor can I in a work of this nature enter fully into 

 the merits of the case, but may be allowed to state briefly the reasons why I 

 have adopted the view that the bark of Catamites was furrowed on its outer 

 aspect, in preference to the opinion that it was smooth. It has also been 

 stated that the specimens of Catamites as ordinarily found are casts of 

 the pith cavity, and that their furrowed surfaces are merely the impress 

 of the inner angles of the vascular cylinder, which, from its more durable 

 texture, was able to resist the decay longer than the delicate pith, 

 which soon disappeared, its place being filled with sediment. Pressure 

 then acting on the vascular cylinder caused the cast of the pith cavity to 

 assume the furrowed appearance. That such specimens do occur there is 

 little reason to doubt, but it appears to me to be equally clear that all 

 furrowed specimens of Catamites are not internal casts of the pith cavity. 

 On large stems we need scarcely expect to find the leaves attached, as 

 probably in the course of nature they were shed before the stems were 

 imbedded, but small branches, with the foliage still in position, are by no 

 means uncommon, and on these, when at all well preserved, the furrows are 

 distinctly seen. Hence it is evident that furrowed stems are not all internal 

 casts of the pith cavity. 



The following plates bear out these remarks : 



Lebour, Illustrations of Fossil Plants, pi. iii. Catamites nodosus. 



Weiss, Foss. Flora d. jUng. Steink. u. d. Eothl. pi. xii. fig. 1, Asterophyllites 



rigidus. 



Steinkohlen-Calamarien, pi. ix. figs. 1, 2, Cingularia typica. 

 pi. xi. Asterophyllites capillaceus. 



pi. xv. Palceostachya elongata. 



Ettingshausen, Die Steinkohlenf. v. Radnitz, pi. vi. Catamites communis. 



Schimper (after Germar), Traite Paleont. Veget. Atlas, pi. xxii. figs. 1-3, 

 Calamocladus equisetiformis. 



Again, if we regard them as casts, how are we to explain the large branch 

 scars on Catamites ramosiw ? It seems most improbable that these large 

 scars were caused by some structure jutting into the pith cavity ; and 

 further, specimens showing the branch attached to the scar are by no means 

 unknown. These arguments prove, I think, that Catamites as they usually 

 occur are not all internal casts. The small tubercles at the top of the 

 furrows are also, I believe, the scar left by the fallen leaf. This is clearly 

 indicated by : 



Ettingshausen, Steinkohlenf. v. Radnitz, pi. i. fig. 5, Catamites communis. 



Weiss, Steinkohlen-Calamarien, pi. xvii. Calamitina GiJpperti. 



Then grant, for the sake of argument, that the carbonaceous layer 

 commonly coating the outside of Catamites, as these usually occur, represents 

 the vascular system and bark, the next point to be considered is whether the 

 furrows have been imparted to a smooth bark by the external rounded 

 surfaces of the vascular wedges, from the pressure exerted during minerali- 

 zation, or whether the furrows are a natural character of the external surface 

 of the stems. This question is more difficult to decide. Any specimens 

 that have been figured showing the structure of the bark do not appear 

 to have been sufficiently well-preserved to settle this point. With all 

 respect to the opinion of those authors who have stated that Catamites had a 

 smooth external bark, I think that the complete proof of the statement has 

 not yet been given. In any figures that I have seen where the bark has been 

 preserved, the flexuous outline they show appears to point more strongly to 

 its having been fluted than smooth. Stems of Catamites also occur, which 

 have not been in any way destroyed by pressure, in so far as they still retain 

 the round form of the stem and on these, too, we find the characteristic 

 furrows. The view which I am at present inclined to adopt, and the one 



