FONTAINE, ] THE EMMONS COLLECTION. 289 
he named Lguisetum columnare. This in its markings is more like the 
imprints made by the exterior of the stems of E. Rogersti above men- 
tioned, but these last do not show the teeth on the sheath as Emmons’s 
figure does in its upper part. The original of Emmons’s figure was 
not seen. His Calamites disjunctus is an imprint of the same nature 
as Calamites arenaceus. 
Genus SCHIZONEURA Schimper. 
ScHIZONEURA PLANICosTATA (Rogers) Fountaine? 
1843. Calamites planicostatus Rogers: Trans. Assoc. Am. Geol. and Nat., Philadelphia, 
1843, p. 305. 
1883. Schizoneura planicostata (Rogers) Font.: Older Mesozoic Flora of Virginia, 
Mon. U.S. Geol. Survey, Vol. VI, p. 14, pl. i, fig. 1. 
One imprint of the interior of a stem was seen that has features 
presented by fossils found in the Older Mesozoic of Virginia, which 
I regarded as probably a new species of Schizoneura, and named it S. 
planicostata. The Williams College specimen has the same kind 
of raised lines or ribs on the imprint. They are decidedly wider and 
stronger than the lines formed by the interior of the stems of Lquise- 
tum Fogersii and appear to belong to a quite different plant. I do 
not positively identify it with S. planicostata, on account of the small 
amount of material. Emmons makes no mention of such a plant. 
Subkingdom SPERMATOPHYTA. 
Subdivision GYMNOSPERMAEF. 
Class CY CADALES. 
Family CYCADACEZ. 
The cycads of Emmons’s collection are the most important type of 
plants both in number of species and in abundance of individuals. 
It is important to note that they are, as Emmons states, found only in 
his upper series, 1,500 to 2,000 feet above the beds that contain coal. 
20 GEOL, PT 9—19 
