CRYPTONEMIACE^E. 193 



Genus LXXXIX. SCHIZYMENIA. 



Frond flat, fleshy, composed of two layers ; the inner of 

 densely interwoven, slightly -jointed threads • the outer of 

 vertical, necklace-like threads. Spore-nuclei immersed in the 

 outer layer of the frond ; tetraspores cruciate, collected into 

 dense sori, also lodged in the outer layer, but in separate 

 plants. — Schizymenta, from the Greek schistos, cloven; and 

 umeen, a membrane. 



There are about a dozen species described as belong- 

 ing to this genus, but only two of them are British, and 

 these have been hitherto known to collectors by dif- 

 ferent and separate generic names. One was formerly 

 the well-known Iridaa edulis, and the other, the less 

 common Kallymenia Dubyi. 



Schizymenia edulis. The eatable Schizymenia. 



Fronds growing in clusters, several from the same base, 

 and varying in size from a few inches to a foot or more in 

 length, and from two to six inches broad, commencing with 

 a short, cylindrical stem, which becomes gradually flat, and 

 expands into an oval, thick, leathery, leaf-like disc. Spore- 

 clusters sunk beneath the external layer of cells in the 

 upper part of the frond, and having the appearance of 

 minute dots ; tetraspores cruciate, lodged in a dense, band- 

 like sorus, just within the periphery. 



This plant, the Iridma edulis of the 'Phycologia 

 Britannica' and other works, seems to have been des- 

 tined to a plurality of names throughout its career. 

 Dr. Harvey mentions no less than six generic, and four 

 specific names for it, and these do not include that of 

 Schizymenia, its present, and I trust its permanent 

 designation. Add to this, tbat it is called edulis, 



o 



