An Overlooked North American Fern

Hooker called this "a very peculiar species of Polypodium (sect. Drynaria, Fee, but probably a Microgramma of Presl)." It does have more resemblance to Microgramma than to anything else, and this may be its affinity, but the rather fleshy, herbaceous texture, and the laxly and irregularly anastomosing veins, and the paucity of included veinlets make it seem unreasonable to include it in that genus. The tubers are remarkable; but I would not regard them as by themselves justifying generic distinction for the species, no more than do those of Nephrolepis cordifolia.