252 FLOEA OF LOWEE COAL MEASUEES OF MISSOURI. 



discussed in the Coal Flora, shows, as there remarked, a segment of Stem- 

 matopteris, about 70 cm. long, the upper part of which is clear, while the 

 lower part is so associated with the leaves of Tceniophylhmi, which stream 

 downward at an angle of about 25° to the trunk, that it seems impossible 

 to decide whether they are not organically united to the trunk. The 

 presence of the Triletes among the leaves seems to have constituted the essen- 

 tial reasons for his conclusion that the leaves of the TcBniopliyUmn were for- 

 eign to the fern trunk. For my own jDart, after a close scrutiny of the trunk 

 I am unable to show that the leaves were not joined to the trunk, although 

 they are found streaming down from one side only. No. 9260, identified 

 by Lesquereux under the same name, shows another unmistakable frag- 

 ment of trunk, associated in the same way with the typical leaves of Tcsnio- 

 phyllum with Triletes and other plant fragments mingled therewith. So also 

 Nos. 9257, 9262, 9265, labeled as T. decurrens, and No. 9272, and apparently 

 9275, marked as T. contextum Lx., present the same phases of association of 

 the leaves with the fern trunk in such a relation as to leave one uncertain 

 as to their union. The circumstantial evidence, including (1) the partial or 

 total obscurity of the Caulopteroid scars in the lower parts of the trunks 

 beneath the bases of the leaves; (2) the apparent impossibility of following 

 any of the leaves from one side of the trunk across and beyond on the other 

 side; (3) the angle of contact of the leaf with the mass of matted bases on 

 the trunk; (4) the direction of the leaves downward, though generally out- 

 ward, and not always on the same side; (5) the similarity of the compressed 

 fragments of axes of TcEniophylUmi on which no Caulopteroid scars are 

 visible with the interpetiolar surfaces of the Stemmatopteris, which are 

 apparently indistinguishable; (6) the blending of the carbonaceous residue 

 of the leaves with that of the superficial tissue of the fern trunk, and (7) 

 the occurrence in No. 9265 of unmistakable Tceniopliylhim leaf scars and 

 good leaves on different portions of a long segment of trunk showing what 

 can hardly be else than somewhat masked scars of Stemmatopteris, are 

 strongly in favor of an organic relation of the leaves with the trunks. 



Against an hypothesis which may presuppose a ramental function for 

 the TcBniophyllum would, on the contrary, seem to stand the branching habit 

 of the leaves, as shown in PI. LXIII, Fig. 4, which I can hardly explain as 

 penetrative rootlets of Stigmaria. Even the epidermal features of tlie leaf 

 itself seem to argue against such a view. Nevertheless, the habit of these 



