432 PALAEONTOLOGY OF ILLINOIS. 



The specimens of this species were found in connection with the Lepdio- 

 phloyos auriculatum and its LepidopJiyHum, as seen in fig. 1, in the roof shales 

 of the main coal of St. Johns. Dedicated to Mr. Thos. Tijou, superintendent 

 of the coal mining company, Duquoin. 



LEPIDODENDRON MAMMILLATUM, Sp. nov. 



PI. XXV, fig 1. 



GENERAL cicatrices marked obscurely by an irregular nar- 

 row furrow, obtuse at the upper end, narrowed downwards 

 into a caudate curved point, central scar round, mammillate or 

 convex, notched at the top, or with irregularly undulate bor- 

 ders. The specimen represents the decorticated part of the 

 species, and does not indicate any trace of leaf scar or of vas- 

 cular points. The surface is deeply and irregularly grooved, 

 the grooves passing in undulations between the cicatrices. 



Found in large specimens on the roof shales of the coal at Morris. 



From specimens obtained two late for the plate, the species shows the char- 

 acter of a true Lepidodendron. The cicatrices are broadly oval, pointed at 

 both ends, the leaf scar is of an oval form, enlarged on the sides or horizon- 

 tally marked with a large medial vascular point and two lateral ones, placed at 

 the corner of the leaf scar under which is an oval convex bolster. This bolster 

 is the oniy part left of the specimens where the surface is old or eroded, as seen 

 in our figure. 



LEPIDODENDRON CRUCIATUM, Sp. nov. 



PI. xxv, fig. 2. 



SURFACE furrowed by deep, irregular grooves, diverging from 

 the scars in quincunxial direction ; cicatrices distant, deeply 

 cut in the shale, but irregular and variable, generally oval and 

 narrowed downwards. The supercortical layer of coaly mat- 

 ter is very thick, one line at least, deeply, narrowly and regu- 

 larly striate, filling the depressions or hollow scars, and oblit- 

 erating their forms. 



The specimen from which the figure is copied, is large, and apparently repre- 

 sents the base of a tree whose bark has become roughened by age. The spe- 

 cies is uncertain and not satisfactorily known. 



Roof shales of the coal at Morris. 



