254 FLOEA OF LOWER COAL MEASURES OF MISSOURL 



dowiiward-ciu'ving- base, glossy iu the compressed state, minutely lineate, 

 about 6 or 7 lines to the millimeter, the primary leaves 4 to 8 mm. wide, 

 branching irregularly at very variable distances, usually singly, sometimes 

 nearly fasciculately, and traversed in the fossil condition by a longitudinal, 

 flexuous, somewhat irregular vascular band or lax strand, about .75 to 1 

 mm. in width, which gives off a division to pass through the small, some- 

 what oval, Stigmarioid attachment into and along each more slender branch, 

 2 to 3 mm. in width, of the primary leaf. 



The sole type on which the above description is based is the large 

 fragment, a portion of the upper part of which is illustrated in pi. Ixxxiv of 

 the Atlas to the Coal Flora. The original specimen, recently presented to 

 the United States National Museum by Dr. J. H. Britts, of Clinton, Missouri, 

 longitudinally traverses a slab 40 cm. in length and 22 cm. in width. The 

 axis is compressed to a thin and somewhat uneven interior cast, which, on 

 account of its variances from the cleavage suiface, is so fractured as to 

 expose portions of the fossil at all its levels, although it is difficult at any 

 point to ascertain its precise width. Thus, as is very imperfectly indicated 

 in the plate just referred to, the upper surface, covered with the imbricated 

 appressed scales, is shown in places, or the impression of the epidermis on 

 the lower side of the stem is exposed, revealing the bases of the scales or 

 their cicatrices, as happens to be the case over the most of the surface 

 included in the figure, while cleavage from the smooth surface of the leaves 

 on the back side of the trunk, or at an angle slightly oblique to the plane 

 of the latter, shows the leaves behind or the matrix beneath the trunk. 

 Such a fracture by a cleavage plane oblique to the axis has, naturally, pro- 

 duced a rounded profile, shown in the figure, at one point in the upper part 

 of the specimen, and this circumstance appears to have given rise to the 

 description of the stems or branches as "tapering up to a conical point."^ 

 Three centimeters farther the broken surface of the slab returns to the level 

 of the upper surface of the stem, which is again found continuing in its 

 normal position and direction, clothed with the appressed scales. The 

 apparent width of the trimk is about 6.5 cm. at the base (assuming that 

 the scales and "leaves" are directed iipward) and nearly the same near the 

 upper end of the segment, indicating no positive diminution. The margin. 



' Coal Flora, vol. ii, p. 557. 



