100 UNITED STATES GEOLOGICAL SURVEY— TERTIARY FLORA. 



a comparatively thick jjellicle of coal, which, cleaved in right angle, appears 

 to have formed by compression the cross-lines visible upon the fragments 

 in figs. 4 and 10. They are not remarked upon the others, which bear 

 more or less distinct, irregular points, seemingly the scars of detached 

 filaments or scales, as in fig. 9. I consider fig. 11 as a fragment of a leaf 

 of this species. It is flat, exactly linear, twelve millimeters broad, doubly 

 nerved; the primary veins are equidistant, one and a half millimeters, the space 

 between being filled by eleven or twelve thin veinlets. The scars in fig 10 pre- 

 sent the peculiar appearance of a row of rays surrounding it, as seen sometimes 

 around the branch-scars of Equisetu?n. From the appearance and difference 

 of characters of the fragments figured, it may be supposed that they belong 

 to different kinds of plants. I believe, however, that they are all of the 

 same species; I found them, and studied them in place, all at the same 

 locality, where, from a number of specimens which have not been figured, their 

 different appearances and characters were seen evidently united by interme- 

 diate forms. 



I was at first disposed to consider this species as identical with Caulin'Ues 

 horealis, Heer (Fl. Arct., i, p. 145, pi. xxiii, fig. 13), which the author sup- 

 poses referable to his C. duhius (Fl. Tert. Helv., iii, p. 170, pi. cxlviii, figs. 1 

 and 2). But the characters do not agree, except perhaps in the round form 

 of the warts, and even these have not inflated borders in our species. Heer 

 figures and describes the stems as very narrowly and equally lined, while, in 

 the American form, they are distantly and irregularly striate ; the position of 

 the warts is not the same, nor are tlie apparent articulations remarked upon 

 the Miocene specimens from Iceland. In the same shale with these frag- 

 ments, I have seen long, ilexuous, ribbon-like rhizomas, fifteen millimeters 

 broad, their surface wrinkled lengthwise, bearing long, linear, flexuous, simple 

 rootlets, three millimeters broad, diverging in right angle. These rootlets 

 come out single and opposite, or in whorls of two to four, from inflations at 

 the point of attachment, and thus produce an appearance of articulation upon 

 some of the primary roots or rhizomas. This agrees well enough with what 

 is seen upon the specimens figured. The fragments in figs. 16 and 17 are of 

 doul)tful reference. The nearly regular position of the scars in rows, and the 

 opposite branches, seem to separate thetn from this species. Saporta considers 

 them as branches of Salishuria. 



Habitat. — Abundant at Black Buttes in the sandstone above the main 



