1862.] DAWSOX DETOXIAN PLANTS. 309 



cylindrical cavity within the bark has been filled with sand and the 

 stems of a small branching Coral, which may perhaps have grown 

 within the hollow bark, which in this case, as in that of the Stig- 

 maricB of the Coal-measures, seems to have been almost indestruc- 

 tible. The specimen is from the Chemung group, at Elmira, New 

 York. 



10. Stigmaeia ncoiDES (variety), Brongniart. 



Large roots of Stigmaria, in some instances with rootlets attached, 

 occur, though rarely, in the sandstone or arenaceous shale near St. 

 John — only two or three specimens having been found. They are 

 not distinguishable from some varieties of the Stigmaria ficoides of 

 the Coal-measures. 



11. DrDTMOPHTLLUM EENIFOKME, Sp. UOV. PI. XIII. fig. 15. 



Areoles prominent, spirally arranged, reniform ; each resembling a 

 pair of small Stigmaroid areoles attached to each other. Areoles 

 YotJi of an inxih in transverse diameter, and about ^th of an inch 

 distant transversely, and ^ths vertically, in a stem ^ths of an inch in 

 diameter. 



The genus Didymophyllum was established by Gceppert for a plant 

 of the Lower Carboniferous series of Silesia, resembling Stigmaria, 

 but with double rootlets. The present plant, though specifically 

 distinct, comes fairly within the characters of the genus. I believe 

 it to have been a slender Stigmaroid root or rhizome, sending out its 

 rootlets in pairs instead of singly. It occurs as a cast with the thin 

 coaly bark in part preserved, and is from the Hamilton group, near 

 Skaneatales Lake, New York. A flattened specimen, apparently of 

 the same species, occurs on a slab from the MarceUus Shale. Both 

 are in Prof. Hall's collection. 



(Qalamitece*.) ' 



12. Calahites Teaksitionis, Goeppert. 

 ' Canad. Nat.' vol. vi. p. 168, fig. 5. 



This species, so characteristic, according to Goeppert, of the Upper 

 Devonian and Lower Carboniferous series in Europe, is abundant at 

 St. John, both in^the sandstone containing Coniferous trees, and the 

 shales which aff'ord Perns, Cordaites, &c. Some of the beds of the 

 latter are fiUed with flattened stems. This was one of the first 

 fossils recognized in the St. John rocks, specimens having been 

 shown to me in 1857 by the late Prof. Robbf. 



A small specimen in Prof. Hall's collection, from the Hamilton 

 group, may possibly belong to this species, though proportionally some- 



* In placing the Calamites here, I do not mean to affirm that all the plants 

 usually included in that genus are gymnospermous ; but I believe that many of 

 them are. 



t Dr. Gesner mentions (' Second Eeport ', 1840, p. 12) a Calamite (probably 

 this species) as occurring near Little Kiver. 



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