104 FLORA OF LOWER COAL MEASURES OF MISSOURI. 



Aphlebia hamulosa (Lx.). 



1879. Rliacophyllum hamulosum Lesquereux, Goal Flora. Atlas, p. 10, pi. Iviii, fig. 3 ; 

 text, vol. i (1880), p. 321. 



The type specimen, No. 9445 of the Lacoe collection, illustrated in the 

 Coal Flora, is the only example of this cm-ious species that I have seen 

 from Missouri. In form it is somewhat suggestive of a Sphenopteris of the 

 group represented by 8. patentissima Ett. This similarity is more apparent 

 in some specimens from Mazon Creek, Illinois. 



The nervation is broad and dense, comparable to Aphlebia spinosa or 

 A. crispa, to the former of which A. hamulosa is closely related, although 

 differing from that species, as was pointed out by Lesquereux, by the bifur- 

 cation of the branches, the recurvation of the divisions, and the slender, 

 long, acuminate points of the lacinese. 



Locality. — Hemy County, Missouri, No. 9445 of the Lacoe collection 

 in the U. S. National Museum. 



Aphlebia spinosa (Lx.). 



1879, Bhacophyllum spinosum Lesquereux, Goal Flora, Atlas, p. 10, pi. Iviii, figs. 4, 5; 



text, vol. i (1880), p. 320. 

 1887. Ehaeophyllum spinostmi Kidston, Foss. Fl. Kadstock Ser., p. 309, pi. xx, fig. 3. 



The main axes and branches of this species are characterized chiefly 

 by the dense, fibrous structure, and the almost totally reduced lamina. 

 The divergent pinnate lateral branches are more regular than in most 

 species of tliis group, and the ultimate lobules are rendered spinescent by 

 the thick traversing bands of parallel, fasciculate, vascular tissue. One or 

 two of the fragments indicate for tlais plant a large size, with a well-defined, 

 uniform, and rig'id rachis. 



The specimen from Radstock, England, figured by Kidston,^ although 

 slightly more robust and less fibrous than the specimen from Missouri, seems 

 to constitute another of the many forms in common between the flora at 

 present under consideration and that so excellently elaborated from the 

 Radstock series. 



The fragments of this species, wliich is, next to Aphlehia German Zeill , 

 the most frequent in the coals of this region, can easily be distinguished 



1 Fobs. Fl. Radstock Ser., p. 309, pi. xs, tig. 3. 



