

CARBONIFEROUS PERIOD. 337 



found to have the characteristics of the Stigmaria; and these roots 

 often lie in great numbers in the under-clays of the coal beds. In 

 Nova Scotia and England, Sigillaria stumps have been observed 

 with Stigmaria roots. Lesquereux, however, maintains that the 

 Stigmariae are sometimes, at least, stems, and not roots. 



Fig. 570 is the Stigmaria ficoides, a species which is said to have a range 

 through the whole Coal measures, — which may be true if more than one species 

 is not confounded under the name. Sigillaria minuta occurs in the Catskill 

 epoch of the Devonian ; other species, in the Upper Coal measures. 



4. Catamites. — These jointed rush-like plants sometimes grew to a 

 height of twenty feet or more, and were associates of the Sigillaria 

 in the marshes, being common throughout the Coal measures. 



Fig. 583 represents C. cannseformis, one of the Lower Coal-measure species. 

 C. Cistii Brngt. and C. nodosus Schlotheim are other American. Lower-Coal 

 species, as well as foreign; C. Pachydermia is found only in the Millstone grit 

 below (Lesquereux). 



5. Conifers. — Coniferous trunks and stumps are common through 

 the Coal measures, and occur also far down in the Devonian. But 

 it is remarkable that their leaves have been seldom found. The 

 Sternbergiaz, which are abundant in Ohio, and at Pictou, Nova Scotia, 

 have been shown by Dawson and Williamson to be casts of the 

 pithy or open cellular interior of some Conifers. (See p. 283.) They 

 are thick, cylindrical stems, much wrinkled circularly, consisting 

 of the same arenaceous material as the rock in which they occur 

 buried. Occasionally they have a carbonaceous exterior, which is 

 the woody part of the former tree. In Nova Scotia specimens, as 

 well as those of England, a coniferous structure has been observed 

 in the coaly exterior, and also a very open cellular structure through 

 the sandstone interior. The Devonian species from Pictou is not- 

 distinguishable in its microscopic structure from the Pinites (Ba- 

 doxylon) Brandlingi of TVitham. 



Most of the known Carboniferous species are related {Dadoxylon 

 included) to the genus Araucarites. The American species of Car- 

 boniferous Conifers have been but little studied. 



Fruits of Conifers and other -plants. — Besides the remains of trunks 

 of Conifers, various fruits are found in the Carboniferous beds. 

 Those which have been referred to the genus Trigonocarpum, accord- 

 ing to Hooker, are the fruit of Conifers, and resemble most that 

 of the Chinese genus Salisburia of the Yeio family ( Taxinece). Ac- 

 cording to Dawson, they are the fruit of Sigillariae. 



Figs. 571 to 574 (by Newberry) represent nuts or fruits from the Lower Coal ; 

 fig. 571 a, b, c, d, is Trigonocarpum trici^ndatum Newberry; «, the nut; b, the 



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