56 



VASCULAR CRYPTOGAMS 



antherids are scattered or in groups, and produce biciliated antherozoids. 

 The archegones appear later than the antherids on the thickened 

 extremities of the same branches. They project above the surface of 

 the prothaUium, and have from three to five canal-cells. In the forma- 

 tion of the sporophyte it is possible that we have a transition between 

 Vascular Cryptogams and Muscinece. The oosphere divides by a wall 

 vertical to the axis of the archegone into two cells, of which the one 

 nearest the neck becomes the suspensor, while the other is the mother- 

 cell of the embryo. The first root is but slightly endogenous. The cells 

 of the prothaUium of all known species of Lycopodium are liable to be 

 infested by an endophytic Pythium, the zoospores of which have very 

 probably been taken for antherozoids. The oophyte of Phylloglossum 



is unknown. Of the development of the spo- 

 rophyte of the Lycopodieae very little is known 

 in its early stages. 



In the typical genus Lycopodium the sporo- 

 phyte resembles Selaginella in habit. The stem 

 of most species is procumbent, extending in 

 the case of L. clavatum (L.) to several feet, and 

 putting out here and there a few roots into the 

 soil. Less vigorous branches rise erect, and 

 are sporangiferous. The procumbent species 

 display a tendency to bilateralness, especially 

 in the structure of the axial ' vascular ' bundle. 

 In other species the much shorter stem grows 

 erect, and puts out roots from its lower portion, 

 which in some cases grow downwards through 

 the tissue of the stem, emerging only as a tuft 

 at its base. In some of these erect species, 

 especially in the tropics, the stem is stout and 

 shrubby. One or two species of Lycopodium 

 have climbing stems ; a few are epiphytic. 

 The sporophyte of Phylloglossum, its only 

 known condition, has a striking resemblance to the embryonic condition 

 of Lycopodium. The erect unbranched stem is very short, rising into 

 a slender scape, which bears at its extremity a spike of sporanges, and at 

 its base a rosette of long subulate leaves ; otherwise the stem bears 

 only a few very rudimentary leaves. The plant is reproduced by adven- 

 titious shoots consisting of a tuber with a leafless rudimentary bud. 



As far as has been at present obser\^ed, the growing end of the stem 

 of Lycopodium has no single apical cell, and the same is true of the 

 leaves and of the roots. The growing point of the stem corresponds 



Fig. 38. — Phylloglossujn Driim- 

 mofidii Kze. /, leaves ; r, roots ; 

 ^1, old tuber ; i^, new tuber : a, 

 sporangiferous axis ( X 3). (After 

 Bower.) 



