BOTANICAL MUSEUM LEAFLETS 
HARVARD UNIVERSITY 
CampridGe, Massacnuserrs, Aprit 28, 1952 VoL. 15, No. 7 
MEDULLOSA OLSENIAE: 
A PERMIAN MEDULLOSA 
FROM NORTH CENTRAL TENAS 
BY 
Davin C. Ropertrs ann Enso 8S. BaArnGHOOoRN 
STRUCTURALLY preserved specimens of the Paleozoic 
seed fern Medullosa are represented in considerable abun- 
dance in the American mid-continent coal fields, where 
remains of the plant in the form of stems, petioles and 
roots are Commonly found in the calcareous concretions 
known as coal balls. Very little information regarding 
the later Paleozoic development of this interesting and 
significant group of plants is available from: .American 
material, although much phylogenetic theory has been 
developed recently as the result of studies of its Carbon- 
iferous representatives (Baxter, 1949: Stewart, 1951). 
In view of the possible phylogenetic significance of geo- 
logically more recent representatives of Medullosa, the 
specimens comprising this study are described in some 
detail. ‘Tothe knowledge of the authors, this description 
ulso constitutes the first report of the genus Medullosa 
from post-Carboniferous sediments of North America. 
The specimens under consideration were found in sec- 
tion 754, Texan Emigration and Land Company Survey, 
10 miles west of Neweastle, Young County, Texas. ‘The 
material collected consists of fragments of decorticated 
stems and one petiole. The material occurred i situ in 
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