272 Rev. J. W. DaAVSon on Calamites. 



XXXIIL— O^i Calamites. By the Rev. J. W. DawSON, 

 LL.D., F.R.S., &c., Principal of M'Gill College, Montreal. 



To the Editors of the Annals and Magazine of Natural History. 



Gentlemen, 



I have read with much interest, in your Number for August, 

 the translation by Mr. Dallas of the observations of M. Grand'- 

 Eury on Calamites and Asterophyllitcs. These observations 

 are especially valuable at a time when views as to the struc- 

 ture and affinities of these plants, at variance with those of the 

 best observers on the Continent and in this country, are being 

 propagated under high authority in England. 



The observations of M. Grand'Eury in the Coal-measures 

 of the Loire accord perfectly in many important points with 

 those which I have made in the Coal-formation of Nova 

 Scotia, where great numbers of erect Calamites are admirably 

 exposed. The mode of growth of these plants is stated almost 

 in the same terms, and illustrated by figures, in my paper on 

 ^' Upright Calamites," in the 'Journal of tlie Geological Society,' 

 vol. vii. (1851) p. 194, and again in my paper on " the South 

 Joggins," in the same Journal, vol. x. (1853) p. 34. My con- 

 clusions are shortly summed up in ' Acadian Geology,' second 

 edition, p. 441. There are only two points in which my ob- 

 servations differ from those of M. Grand'Eury. In none of 

 my specimens were there long horizontal rhizomes, the secon- 

 dary stems budding almost directly from the primary. I have 

 not seen a horizontal rhizome longer than a few inches. This, 

 however, is a point of little importance, and might depend on 

 diversity of species or of circumstances. A point of more 

 consequence is that M. Grand'Eury has not seen leaves at- 

 tached to any of his erect stems. I do not wonder at this, 

 because the leaves occur very rarely ; and when present, it is 

 often difficult to trace them in the case of erect stems. I have, 

 however, found leaves actually attached to the stems referred 

 by me to three of the species usually recognized, viz. G. Cistu, 

 C. Suckovu, and C. nodosus. In the former they are long and 

 aciculate, in the two latter they are borne in whorls on verti- 

 cillate branchlets. I have specimens clearly illustrating these 

 facts, and can affirm, on the one hand, that the true Calamites 

 had leaves, at least on some parts of their stems, and, on the 

 other, that these leaves are quite distinct from those which 

 properly belong to the genera Aster ophyllites^ Anmilari'a, and 

 Sphenopki/llum. Beautiful specimens, showing the structure 

 of the stem, enabled me to show, several years ago, that the 

 last-named plants resemble Ferns and Lycopodia, not Gala- 



