BRYOPHTTA. 87 



The leaves (Fig. 52, A, B) are rounded in outline unequally, 

 two-lobed, and arranged in two rows on the upper side of the 

 stem, so closely overlapping as to conceal it entirely. On the 

 under side are similar but smaller leaves, less regularly dis- 

 posed. The stems branch at intervals, the branches spreading 

 out laterally so that the whole plant is decidedly flattened. 

 On the under side are fine, whitish hairs, that fasten it to the 

 substratum. If we examine a number of specimens, especially 

 early in the spring, a difference will be observed in the plants. 

 Some of them will be found to bear peculiar structures (Fig. 



* 3) 



FIG. 52. A, part of a plant of a leafy liverwort (Madotheca), x 2. B, part of 

 the same, seen from below, x 4. C, a branch with two open sporogonia (sp.), 

 x 4. D, a single sporogonium, x 8. 



52, (7, D), in which the spores are produced. These are called 

 " sporogonia." They are at first globular, but when ripe open 

 by means of four valves, and discharge a greenish brown mass 

 of spores. An examination of the younger parts of the same 

 plants will probably show small buds (Fig. 54, H), which con- 

 tain the female reproductive organs, from which the sporogonia 

 arise. 



On other plants may be found numerous short side branches 

 (Fig. 53, .B), with very closely set leaves. If these are care- 

 fully separated, the antheridia can just be seen as minute 

 whitish globules, barely visible to the naked eye. Plants that, 



