202 THE JOURNAL OF BOTA.NY 



forms of animal life of the same ponds, culminate on the bodies of 

 higher modern insects which may attain wholly subaerial habits. In 

 contrast with the minimum soma of the Laboulbeniacese, reduced to 

 vestigial juvenile phases, as it becomes regulated to the short life- 

 period of the insect-host and the time-factors of insect-life \ the 

 Lichen retains form-factors and the relics of tissue-differentiation of 

 an equally high-grade and massive series of plant-forms ; and the 

 story of one divergent group amplifies that of the other, to the extent 

 that the two together open up vistas of older algal races of the sea, 

 beyond the confines of the few widely divergent and residual series 

 seen in modern seas as Brown and Red seaweeds. Similarly, the 

 reproductive story of the Lichen does but cover the same ground, and 

 the same sequence of biological progression that has been already out- 

 lined from consideration of the form-factors of the vegetative soma 

 alone. In all cases the algal outlook is essential, and is now seen 

 to be the only one capable of binding the whole story into one unified 

 scheme of progression ; as the outlook of the mycologist, systematist, 

 or collector, tends merely to place these vestigial races of an older 

 world in watertight compartments, with no direct connection with 

 each other, as a retention practically of an older outlook of special 



creations. 



(To be continued.) 



NEW OR RARE BRITISH HEPATICS. 



By William Edward Nicholson, F.L.S. 



Riccia. Huebeneria.'NA Lindenb. During the warm sunny 

 autumn of 1919, when the mud of the large pond at Horsted Keynes, 

 Sussex, had been uncovered for a long time, I gathered on some of 

 the more exposed parts of the mud, where I had frequently found 

 Riccia pseudo-Frostii Schiffn., several rosettes of a deep violet 

 Riccia, which I am unable to distinguish from R. llaeheneriana. 

 On cutting transverse sections of the frond. I found these agreed 

 closely vvitb the figures of the frond-section of this species as given by 

 Karl Mueller (Die Lebermoose, 1st Abl. p. 20G). The rosettes are 

 a little more compact and have shorter branches than in my Con- 

 tinental specimens, but the differences are not material, and I do not 

 think that there can be &r\y question as to the identity of the plant. 

 In spite, however, of rather striking differences between characteristic 

 specimens of R. Huebeneriana and R. pseudo-Frostii, there are 

 perhaps reasons for questioning whether they are really specifically 

 distinct. Schiffner first separated It. pseudo-Frostii only as a variety 

 of R. Huebeneriana, and finally elevated it to the rank of a distinct 

 species, principally on account of the larger size, the different appear- 

 ance of the much greener rosettes, which are only faintly tinged with 

 violet, and the winged thallus, as seen in transverse section. Certainly 

 these characters, especially that drawn from the section of the thallus, 

 which is generally one of the most trustworthy in this difficult 

 genus, appear to warrant Schiffner's later opinion, but on careful 



1 Tbaxter (1896L p. 240. cf. Stigmatomyces on flies, mature in 10-14 days ; 

 the time-factor thus giving the clue to the arrest of the soma at a ' juvenile 

 etRg* 1 .' 



