48 AMERICAN FERN JOURNAL 
ISOETES SACCHARATA Encetm. Shallow water be- _ 
tween tides, in gravel and sand; banks of the Potomac 
between Alexandria and Mount Vernon; variable, sev- 
eral forms having been described. — 
Wasuineton, D. C. 
The Simplest Fern in Existence 
R. C. BENEDICT 
What is the simplest fern in existence? It is not Asplen- 
ium Trichomanes with its short wiry midrib and small 
pinnae. It is not even Trichomanes Petersii with not 
much more than a pinna of leaf tissue and leaves one cell 
thick. These are perhaps the simplest ferns in the 
United States from the standpoint of size and structure. 
The simplest known fern is a native of the tropical East 
Indies, a species of the genus Monogramme Schkuhr, M. 
dareaecarpa Hooker. 
In this plant, each leaf has but one vein and one fruit 
dot or fruiting line, set in a groove along one side of the 
leaf. The placing of the sporangia was responsible for 
the original specific name, dareaecarpa, after Darea, & 
group of ferns generally placed under Asplenium. The 
plants are epiphytic and grow mixed with mosses on the 
bark of trees. The stem, like the leaf, has a single solid 
wood fiber traversing it, only a few cells thick. 
The relationship of Monogramme is with the fern tribe 
Vittarieae. Vittaria, a single species of which, V. line- 
ata, occurs in Florida, always has two lines of sporangia 
while Monogramme has but one, but in venation, the 
largest species of Monogramme is almost a duplicate of 
the smallest Vittaria. 
The other species of Monogramme are almost as simple 
as M. dareaecarpa. The first species discovered, M. 
graminea, from the Bourbon Islands off the coast of 
Africa, is like M. dareaecarpa, but with leaves three or 
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