444 INTRODUCTION TO CRYPTOGAMIC BOTANY. 



III. JUNGERMANNIACE^, Lind. 

 JUNGERMANNIEiE, Necs, Endl. 



Fruit solitary. Sporangia splitting into four equal valves. 

 Spores mixed with elaters. 



488. We have hitherto had nothing in MUSCALES resembling 

 a stem with foliaceous appendages, with the exception of Riella 

 (Fig. 90, d), and in this case the leaf was a mere wing run- 

 ning round the stem. There was, indeed, a midrib in Mar- 

 chantiaceoi, which manifested its importance by either giving 

 rise directly to the fruit, or by the fruit proceeding from the 

 point of bifurcation of the frond to which the midrib led, and 

 which might be considered its point of most active vegetation. 

 We have here, in the majority of cases, the most distinct stem 

 with well-marked, symmetrical, often bifarious, leaves and 

 stipules, though we begin with cases in which the frond is still as 

 Lichenoid as before. The leaves, however, as yet assume little of 

 the character or appearance of those of Phasnogams in general. 

 Their forms are mostly grotesque, with strange appendages, 

 and in a few cases only assume simple, oblong, ovate, or lance- 

 olate outlines. On the contrary, many of the strange forms 

 assumed by the leaves of Phaenogams have their counterpart 

 among Jungermannice. Sometimes they are reducedto a few 

 short confervoid threads, or even where the stem is developed 

 vanish altogether ; added to which, though under certain cir- 

 cumstances of a pure green, they are inclined to be shaded 

 with red, purple, chocolate, or other tints. 



489. The leaves are disposed after two different plans, 

 according to which they have received the nam.e of succubous 

 or incubous. In the former case they are disposed in a spiral 

 which turns from left to right, and consequently the anterior 

 border of each inferior leaf is covered by the posterior border 

 of that immediately above (Fig. 94, b). In the latter, the spiral 

 turns from right to left, and the anterior border of each inferior 

 leaf covers the posterior border of the leaf placed immediately 

 above it (Fig. 94, a)* Besides these there are ventral leaves, 



* In Mitten's Conspectus, in the Flora of New Zealand, Gottschea is 

 placed in the incubous series, for the anterior margin really goes over 



