325 



the most useful and original work upon British Cryptogamic plants that we 

 yet possess, is clearly in a similar state of uncertainty ; and Agardh admits 

 nothing more in them than a reseml)lance to male organs, adopting the 

 opinion that they are a particular form of gemmules. The bodies iving in 

 the cup-shaped receptacles of Anthoceros have been said to be anthers, 

 but upon no good evidence. In Jungermannia there is a third kind of re- 

 productive matter, consisting of heaped clusters of little amorphous bodies, 

 growing from the surface of the leaves, and called gemmse. 



The most remarkable point of structure in Hepaticse is the spiral filament, 

 as it is called, lying among the sporules within the theca. This consists of a 

 single fibre, or of two, twisted spirally in different directions, so as to cross 

 each other, and contained within a very delicate, transparent, perishable tube. 

 They have a strong elastic force, and have been supposed to be destined to aid 

 in the dispersion of the sporules, — a most inadequate end for so curious and 

 unusual an apparatus. It is more probable that they are destined to fulfil, 

 in the economy of these plants, some function of which we have no knowledge. 

 Hepaticse are intermediate between Mosses and Lichens, agreeing with the 

 former in the presence of a distinct axis of growth, and frequently of leaves 

 also, and in most cases in the sporules being contained in stalked thecae, 

 having a calyptra and a definite mode of dehiscence. Fee says they have 

 no calyptra, which must have been an oversight. They differ from Mosses in 

 the want of an operculum, by which Andraea, which forms the link between 

 Hepaticse and Mosses, is referred to the latter. Lichens are distinguished 

 by their want of a distinct axis of growth, by their texture and colour, never 

 assuming the rich lucid green of Hepaticoe, and by their sporules not being 

 contained in distinct thecse, but lying in membranous tubes or asci in the 

 substance of the thallus. Riccia and Endocarpus form the connexion be- 

 tween them. 



Geography. Natives of damp shady places in all climates; two were 

 found in Melville Island. The only atmospheric condition to which they 

 cannot submit is excessive dryness : thus, of the 237 species enumerated by 

 Sprengel, 6 only are found in Africa, while 50 are cited from Java alone. 



Properties. Nothing is known of them. Decandolle thinks it pro- 

 bable that the larger kinds will be found to resemble foliaceous Lichens in 

 their qualities. A few are slightly fragrant. 



Examples. Marchantia, Targionia, Sphgerocarpus, Jungermannia. 



CCLXIX. CHARACE^. The Chara Tribe. 



Charace.?:, Rich, et Kunth in Humb. et Bonpl. N. G. PL 1. 45. (1815) ; A. Brongn. 

 in Diet. Class. 3. 474. (182.'}); Grev. Fl. Edin. xvii. (1824); Dec. and Dulnj, 533. 

 (1828) ; Hooker Brit. Fl. 459. (1830.) 



Diagnosis. Submersed leafless water-plants, having slender verticillate 

 branches and deciduous thecse. 

 Anomalies. 



Essential Character — Plants composed of an axis, consisting of parallel tubes, 

 which are either transparent or encrusted with carbonate of lime, and of regular whorls of 

 tubes, which may be either considered as leaves or liranches. Organs of reproduction, 

 round succulent globules., containing filaments and fluid ; and axillary nucules, formed of 

 a few short tubes, twisted spirally around a centre, which has the power of germinating. 



