184 FLOEA OF LOWER CO^.L MEASURES OF MISSOURI. 



equally or unequally at a narrow angle, leafy, tapering plumose to the tufted 

 apex ; nodes prominent, generally very short, 1 to 6 mm. distant, frequently 

 crowded near the base of the branch, each provided with a verticil of 

 leaves; leaves 6 to 12 in the verticil, united usually in six pairs in the smaller 

 twigs, the members of each pair being joined for a distance from the base by 

 their lamina?, or even the pairs joined to one another for a short distance when 

 young, and separating with the increased growth of the axis, lanceolate, 

 2.5 to 8 mm. long, tapering from near the base to the acute apex, slightly 

 carinate, not regularly alternate from node to node, minutely rugose, oblique, 

 or erect when young, at the point of attachment, then curving- outward, ofteu 

 more or less reflexed according to age and position, then turning upward 

 and sometimes slightly inward, approaching a semi-uncinate form, some- 

 what thickened at the slightly constricted base, nearly smooth or obtusely 

 carinate on the arching dorsal surface ; median nerves of each jjair of leaves 

 simple at the base, or distinct and separate, converging to contiguous points 

 of origin, relatively broad, dorsally lineate-rugose under the lens; strobili 

 borne on the branches, 6 to 25 mm. long, 5 to 7 mm. wide, divided into 

 nodes about 2 mm. apart, the axis being- 1.25 mm. wide, ribbed like the 

 branch, each node bearing a verticil of bracts slighth' longer than the pre- 

 ceding leaves, somewhat strongly reflexed, then curving upward at the 

 middle and finally turned inward; sporangia slightly oval, the g-reater 

 diameter being a little less than 1 nnn. 



A number of typical specimens, some of which are from the type 

 locality, bring to our attention new features in this unique and interesting 

 species. 



The common aspect of the plant is indicated in pi. iii, fig. 1, of the 

 Coal Flora by Professor Lesquereux, though the habit of the leaves is not 

 there shown so well as in our PL L., Figs. 2 and 3. On my first examina- 

 tion of the species I was disposed to regard the dichotomous fasciculate 

 specimens as specifically distinct from the form illustrated in fig. 2 of the 

 Coal Flora plate. I have seen no other specimen from this region with 

 such an aspect of ligidity, which is exaggerated in the figure, and with the 

 appearance of opposite branching, except the original of that figure, now 

 No. 8292 of the Lacoe collection in the United States National Museum. 

 This original diff'ers, furthermore, from the figure by the much more falcate 

 character of the leaves, A^-hich are more open at the l:iase, then cur^^ng 



