TO.,.. 



PRB-CARnONIFEROUS PLANTS. ' ^L 



ft 



regular arrangomont of tho cells in radiating aories and in thoir want of 

 spiral structure. It would bo difficult to distinguish this genus in obscure 

 or badly preserved fragments, from Prototaxitea on tho one hand or 

 Dadoxylon on the other. For this reason, in ray former paper, I placed 

 with some diffidence in the genus Aporoxylon certain fragments from New 

 York and from Maine which presented at least the negative characters 

 of the genus. I have not as yet been able to obtain any further specimens 

 \\' , enabling mo to bo more confident on the subject. 



Casts of Pith-Cylinders. 



9. Sternberoia. Sp.— (PI. Ill, Figs. 28, 29.) 



Those transversely marked casts of pith-cylinders are now known to 

 have belonged to trees of several different genera, e. g. Dadoxyhn, Sigil- 

 laria, Lepidodendron, Leptophleum. 1 figured in my paper of 1861 and 

 more recently in Acadian Geology, 2nd edition, the Sternbergia pith of 

 Dadoxylon Ouangondianum, found in the interior of the calcified stem. . 

 In my paper of 1862 (J. G. S., XVIII), I showed that Leptophleum 

 rhomhicum has a similar pith. I have since obtained specimens collected 

 by Mr. Matthew at St. John, and by Mr. Weston at Lepreau, showing 

 similar casts, entirely denuded of the wood in which they were no doubt 

 at one time enclosed. To what plants they belonged I do not know, but 

 they sufficiently resemble the pith of Dadoxylon Ouangondianum to render 

 it possible that they represent trunks of that species which have perished 

 by decay. They may however have belonged to stems of Leptophleum. 



(Sigillarice.) , . 



Genus Siqillaria. — Brong. ' ' ' ' 



10. Siqillaria palpebra, Dn.— J. G. S., XVIII, 307 ; PI. XIII, 

 Fig. 12. — M.D., St. John, New Brunswick. 



^* Ribs narrow, about a quarter of an inch in width. Leaf-scars transversely 

 acuminate, small. " 



11. Sigillaria Vanuxemii, Goeppert. — Flora Silurisch, &c., p. 546. 

 J. G. S., XVIII, 307 ; PI. XII, Fig. 7.— U. D., Oswego, New York. 



•" Areoles hexagonal, rather longer than broad. Vascular scars indis- 

 tinct, apparently two in each areole. Bark thick. Ligneous 

 '^} surface obscurely ribbed, with small elongated scars in the furrows. 

 --• f Woody axis sulcated longitudinally; its diameter equal to one- 

 fourth that of the stem. There are about twelve rows of areoles 

 on a stem half an inch in diameter." 



U» 



