VIIl] 



DETERMINATION OF LIVERWORTS. 



231 



body. Such genera as Pellia, Marchantia, Lunularia, RebouUa, 

 and others bear a striking resemblance to Fucus, Ghondrus and 

 many other algae. 



Imperfect specimens of certain Lichens, not to mention 

 some of the Polyzoa, might easily be mistaken for Liverworts. 

 Among the higher plants, there are some forms of the Podo- 

 stemaceae which simulate in habit both thalloid and foliose 

 Liverworts as well as Mosses \ The members of this Dicoty- 

 ledonous family are described as water-plants with a Moss- or 

 Liverwort-like form ; they occur on rocks in quickly-flowing 

 water in the tropics. In one instance a recent Podostemaceous 

 genus has been described as a member of the Anthocerotales ; 

 the genus Blandowia'^, referred to by Willdenow as a Liverwort, 

 has since been recognised as one of the Fodostemaceae. The 

 resemblance between some of the foliose Hepaticae and genera 

 of Mosses is often very close. In certain Mosses, such as 

 Hookeria pennata^, the large two-ranked leaves suggest the 

 branches of a Selaginella. 



Fio. 48. A. Tristichia hypnoidea Spreng. From a specimen in the British 

 Museum. B. Podocarpus cupresnna Br. and Ben. (After Brown and 

 Bennett^.) C. Selacfhwlla Oregana Eat. From a plant in the Cambridge 

 Botanic Garden. A, B and C very slightly reduced. 



1 Hooker, J. D. (91) p. 513. 

 3 Hooker, W. J. (20) PI. clxiii. 



2 Schiffner (96) p. 140. 



* Bennett and Brown (88), PI. v. 



