48 



FOSSIL COAL PLANTS. 



# 



Nucleus heart shaped, obtuse, with cicatrix at 



base, strongly rugouse or tubercular, bordered 



by a very narrow striated margin. Sternberg's 



Fig. 8. figure is more rounded at the apex than our fossil 



C. Retusum. ° ^ 



carpoiithes generally is, and is destitute of the striated mar- 



Retussis, . ": 



Sternberg, gin. I have specimens, however, which agree 

 precisely with his figure. 



J 



Fig. 1.— S. Acuminata. 



SIGILLARIA ACUMINATA. 



Trunk ribbed, 

 ribs parallel, mod- 

 erately elevated, | 

 inch wide, each rib 

 divided into five 

 bands or stripes, of 

 which the central 

 is most prominent, 

 widest, rugous and 

 of unequal width, 

 being contracted 

 ^^ above theleaf scars 

 and expanded be- 

 low them ; lateral stripes striated longitudinally. Cica- 

 trices pyriform, abruptly rounded below, often truncated, 

 above crowned by a long claw-like appendage, which 

 is sometimes bifid. Vascular impressions low down in 

 the leaf-scar, two exterior straight, or slightly curved, 

 central punctiform. Decorticated trunk ribbed, smooth, 

 marked b}'' linear depressions under the leaf-scars of the 

 exterior. 



In obscure specimens the acuminate appendage of the 

 leaf-scar is hardly i)erceptible. In this state it greatly 

 resembles ^S*. rugosa, Brong., differing from that species, 

 however, in the low place of the vascular impressions, and 

 in the variations of the width of the central rugose stripe. 



In shale over coal, Cuyahoga Falls. 





