470 PALAEONTOLOGY OF ILLINOIS. 



larger and more distant from each other. The form of the 

 pinna and of its division is also totally different in our species. 



Mazon creek ; S. S. Strong. 



A number of specimens, representing fruiting pinnae of Pecopteris or Ale- 

 thopteris, have been recently obtained from Mazon creek, but are left unde- 

 scribed, tbe essential characters, form and position of the son', nervation, etc., 

 being too obscure for a satisfactory diagnosis. 



HTMENOPHYLLITES FTJRCATUS, Brgt. 



Veg. Foss., p. 179, PI. 49, fig. 4 and 5. 



A few small specimens of this species have been collected by Mr. S.'S. Strong, 

 from the roof shales of Morris. It is rather a sub-conglomerate species, being 

 found most abundant at the base of the mill-stone grit, or the top of the red 

 sandstone, in the anthracite basin of Pennsylvania. 



STIGMARIOIDES ? RUGOSUS, Sp. nov. 



As much as can be seen from two specimens obtained in con- 

 cretions at Mazon creek, by Mr. S. S. Strong, the stem is cy- 

 lindrical, two to three inches in diameter, marked with circu- 

 lar depressions, points of insertion of branches, or rootlets di- 

 verging from it all around, enlarged at base, cylindrical, flat- 

 tened by compression, tapering or diminishing in size from the 

 base, half an inch broad to the top, one-fourth of an inch in 

 diameter, where these rootlets are broken, two and a half 

 inches from the points of insertion. Their surface is wrinkled 

 and narrowly striate in their length, and marked by small 

 round holes, which appear as the basilar points of attachment 

 of branches of rootlets. The cross section of half a cylindri- 

 cal stem is obscurely seen, and appears to be marked by broad 

 tubercles like those of a stem of a Calamites, only much lar- 

 ger. There is nothing published as yet, which can compare 

 with these fossil remains, but the roots of Equisetum Mougeotii, 

 Schp., Pal. Veg., pi. 13, fig. 9. I consider them as represent- 

 ing the rhizomas of some Equisetacece. 



