BRIEF ER AR TICLEES 
SAGENOPTERIS, A MESOZOIC REPRESENTATIVE OF THE 
HYDROPTERACEAE 
(WITH ONE FIGURE) 
The question of the botanical relationship of the genus Sagenopteris 
has been a debated one for a great many years. The genus was founded 
by PreEst in 1838 for a Rhaetic (upper Triassic) form from south Ger- 
many, and since that time a considerable number of species have been 
described from all over the world, all of which come from rocks of Meso- 
zoic age. The genus has been discussed by ScHIMPER, NATHORST, 
Berry, and Sewarp. Nearly all students have recognized its pteri- 
dophytic affinities, and many have suggested a relationship with the 
so-called water ferns (Hydropteraceae). NATHORST was the most 
emphatic advocate of the latter relationship, which was based upon 
habit and venation of the vegetative parts. He fortified it by his dis- 
covery in the Rhaetic beds near Palsjé in Sweden of fruitlike bodies, 
which, aside from their resemblance to the sporocarps of the modern 
Marsiiea, did not represent the fruits of any known Coniferophyte or 
Cycadophyte present in the Rhaetic flora of Sweden, and therefore were 
considered to be the sporocarps of Sagenopteris, being found in associa- 
tion with the fronds of S. undulata Nathorst. 
Somewhat similar remains, considered to represent the sporocarps 
of Sagenopteris, have been recorded by Z1cno from the Jurassic of Italy, 
and by Heer from the Upper Cretaceous of western Greenland (HEER 
referred the latter to Marsilea). In describing the Lower Cretaceous 
of Maryland in ro11, I considered the evidence sufficiently good to 
warrant referring the Potomac species of Sagenopteris to the Hydrop- 
teraceae. The most abundant of these Potomac species, and the only 
one at all well characterized, namely S. elliptica Fontaine, has been found 
to have a considerable geographic range. It is not only present in the 
Patuxent formation (the oldest member of the Potomac group), but 
occurs also in the Patapsco formation, which there is good evidence to 
consider to be of Albian age. This species has also been recorded from 
the Knoxville and Horsetown beds of California, the Kootenay formation 
of Montana, and the Lower Cretaceous of Queen Charlotte Islands. 
Botanical Gazette, vol. 74] [329 
