18 GUIDE TO CRYPTOGAMS. 



Aneura. Sporangium borne on under side of thallus near the 

 margin ; elaters unispiral, adherent to the apex of the valves. 



ANTHOCEROTACE^. We have only the two following 

 genera, and these are not very common : — 



Anthoceros. Capsule linear or cylindric-oblong, bivalved. 



Notothylas. Capsule very short, included in the involucre, 

 oblong-spheroidal, compressed or ovate-cylindric, stalked, the 

 stalk arising from a thickened bulb, the suture breaking in small 

 pieces. 



MARCHANTIACE^. The following two genera are very 

 common : — 



1 a. Gemmce in crescent-shaped receptacles on the back of the 

 thallus. 



Lunularia. Thallus oblong, with roundish lobes, distinctly 

 areolate and porose. Scales imbricate, sub-lunulate, their apex 

 abruptly contracted into a roundish cochleariform lobe. (Intro- 

 duced into green-houses, where it is always sterile.) 



1 b. Gemmod in cup-shaped receptacles. 



Marchantia. Fruit pendant from the under surface of a 

 large, stalked, 7 — 9-rayed carpocephalum. Inner involucre 4 — 

 5-lobed. 



RICCIACE^l. The following is our only common genus : 



Riccia. Fruit immersed in the thallus, sessile. Spores sep- 

 arate from one another. Thallus at first radiately divided from 

 the centre, which often soon decaj's ; the divisions bifid or di- 

 trichotomous, plane, depressed or canaliculate above, and usu- 

 ally convex and naked or squamulose beneath ; margins either 

 naked or spinulose-ciliate, epidermis usually distinct. 



ALG^E. Orders : 

 1 a. Multicellular. 

 2 a. Color red or reddish purple, rarely blackish, in fading 

 becoming at times greenish. 



