and Polyides rotundus. 97 



length = 0-01 15'" par. ; breadth = 0-0035'" par. ; b, the inner part, 

 now and then wanting, breadth : length = 1 : 2-4; absolute length 

 = 0-0303'" par. 2ndly. Oval or elliptical horizontal cells with 

 colourless, roundish grains ; breadth : length = 1 : f-3 ; absolute 

 length = 0-0303'". 3rdly. Cylindrical or elliptical cells, joined 

 at the ends, running in all directions, but more or less perpen- 

 dicular upon the axis of the stem, now and then with colourless 

 roundish grains ; breadth : length = 1 : 3-8 ; absolute length 

 = 0-0377"'. 4thly. Cylindrical perpendicular cells of equal thick- 

 ness in all parts, filled with a slimy mass; breadth : length =1 : 

 15-20; absolute length =0-1 165'". Base, discs, growing points 

 and horizontal stems composed of curved long cells, similar to 

 the third sort of the stem, but filled with brownish grains. All 

 intercellular spaces in the whole frond filled up with a colourless 

 slimy (?) matter. Fruit of two sorts on difi'erent plants in apical, 

 cylindrical-lanceolate sporangia : 1st, zoned tetraspores; 2ndly, 

 elliptical, large, uncoloured cells, containing a great quantity of 

 irregularly-shaped brown spores. 



Polyides rotundus. 



One disc of fixation, from which the frond arises. Frond con- 

 sisting of cylindrical, dichotomous, cartilaginous, solid stems, 

 containing four sorts of cells, the walls of which are colourless or 

 slightly tinged brown. 1st. The epidermal horizontal stratum 

 with brown grains attached to the walls : a, the outer part 

 consisting of 4-5 radiating layers; breadth: length = l : 1-2; 

 average absolute breadth = 0-0041"', length = 0-0050'" par. 

 h, the inner part; breadth : length =1 :2-4; absolute length 

 = 00278"'. 2ndly. Oval or elliptical horizontal cells, with co- 

 lourless, transparent, free grains ; breadth : length = 1 : |-3; abso- 

 lute length = 0-0278"'. 3rdly. Elliptical or cylindrical cells form- 

 ing slanting strings ; breadth : length = 1 : 3-8 ; absolute length 

 between 0"0160'" and 0-0510'". 4thly. Long, perpendicular, 

 femur-shaped cells thicker at the ends than in the middle ; 

 breadth : length = 1:8-15; absolute length = 0-0934'". The disc, 

 the base of the stems, the growing points consisting of curved, 

 long cells, filled with brownish grains. All the intercellular 

 spaces of the whole frond filled up with a colourless, slimy (?) 

 matter. Two kinds of fruit : 1st, crosswise parted tetraspores 

 in the swollen upper parts of the stems ; 2ndly, colourless cells 

 with a great quantity of crimson, radiating, pear-shaped spores ; 

 these cells being imbedded in protuberances on the sides of the 

 upper part of the branches, which protuberances, having no epi- 

 dermis, consist of undivided, nearly parallel strings of cells ; 

 breadth : length = 1 : 1-6, filled with a granular whitish matter. 



I cannot conclude without expressing my warmest thanks to 



