4 POSSIL PLANTS. 



west of Wigan, I stated^ " In the course of his examination of upright stems of Siyillarice 

 in the Coal-measures, the writer has nearly always found Calamites associated wath them. 

 At St. Helenas they were abundant, and their bases were found in contact with the main 

 roots of Sigillarice. One of the authors of the ' Fossil Flora/ Mr. Hutton, in describing 

 the Burdiehouse fossils, at page 24, vol. iii, of that work, states as follows : — Amongst 

 vegetables the characteristic fossils of this deposit are Lepidostrobi, Lepidophyllites, 

 Lepidodendra, and Filicites ; the rarity of Calamites, which occur but seldom and of a 

 diminutive size, and the almost entire absence of Stigmaria, are very striking to those 

 who are accustomed to view the fossil groups usually presented by the beds of the Carbo- 

 niferous formation ; whilst the profusion of Lepidostrobi and Lepidophyllites, of various 

 sizes and various stages of growth, associated with the stems of Lepidodendra, and those 

 of no other plant, is an additional argument for the opinion, which has always appeared 

 highly probable, that they were the fruit, leaves, and stem of the same tribe of plants. 

 Of Sigillaria, a plant which in the flora of the Carboniferous group generally is of so 

 much importance, we could not observe a trace. 



" In the course of his own observations the writer has never yet been able to meet 

 with a stem of Sigillaria of so small a size as six inches in diameter,^ or a Calamites of 

 so large a size as that. Doubtless there must have been young SigillaricB, w^iether or 

 not there were large Calamites. Now, what are young Sigillarim ? This is a question 

 which yet remains to be answered. 



" It is now admitted that little is known about the true nature of the genera Sigillaria 

 and Calamites, except that they were not the hollow succulent stems which they were 

 once supposed to be. 



" The rootlets of Calamites, as previously shown, if not actually identical with, at 

 least very much resemble, those of Sigillaria. In some specimens of the former genus, 

 especially of the species approximatus, figured and described in pi. ccxvi, vol. iii, 

 of the ' Fossil Flora,' and the cruciatus, figured in pi. xix of Brongniart's ' Histoire 

 des Vegetaux fossiles,' their rootlets were arranged in regular quincuncial order. 

 In the largest Calamites that to my knowledge has been figured, namely, that called 

 gigas, pi. xxvii in Brongniart's work before alluded to, the ribs and furrows begin 

 to appear very like those of Sigillaria, and the joints show indistinctly. The termination 

 of the root of a Calamites is exactly of the same form as the terminal point of a Stigmaria, 

 both being club-shaped. 



" I am not aware that up to the present time much, if anything, is known of the 

 structure of Calamites ; but if it should resemble that of Sigillaria, it may tend to prove 

 that Calamites are but young Sigillarim. In our observations it must not, however, be 

 lost sight of that no central axis or pith has, to my knowledge, yet been discovered in 

 the stem of Calamites like that found in Sigillaria. Both plants are proved to have 



1 Since the writing of this paper the author has seen in the Museum at Dudley a stem hke that of 

 a Sigillaria not more than seven inches in diameter. 



