298 NOMENCLATURE OF THE BRITISH HEPATICE. 
At the time when Gray published his work, the Hepaticm were re- 
ceiving considerable attention from various Continental botanists. This 
was undoubtedly owing, to a considerable extent, to the accurate and 
beautiful drawings published by (Sir) Wm. J. Hooker, in his 'Eritisli 
Jungermanniffi ' (1816), and * Musci Exotici' (1818-1820). The 
learned author did' not subdivide the large genus Jmgermamiia, as 
Le considered the fructification too uniform to supply characters suffi- 
cient to establish different genera. He, however, iu the introduc- 
tion to his volume, indicated several groups which have subsequently 
been considered of generic value, such as — Martinellius, Gray {Radula, 
Dumort.), Zejeuuia, Libert, {Pandulphinius, Gray), and Frullania, 
Eaddi, {Salviatns, Gray) ; and iu the ' Clavis analytical which he pre- 
fixed to the description of the species, he grouped together many sets 
of species which are now united into genera. 
Eaddi was the fii'st to deal wdth the subdivision of the genus Jun- 
german7iia. In 1818 he established Reboidia and Fegatella (Opusc. 
Scientif. di Bol. ii.), and in 1820 he added the genera Metzgeria, 
Pellia, Fossombronia, Frallania^ Calypogeia, Roeineria {Riccardins, 
Gray), and Bellincinnia and Antoirea (= Madotheca, Dura.). In the 
same year Mdlle. M. A. Libert established the genus Lejeunia (Ann. 
Gen. dcs Sc. Phys. et Nat. vol. vi.). 
Unaware'of w^hat had been done by Raddi and Libert, Gray arranged 
the whole family into genera 5 and the best testimony that can be borne 
to the clear perception he had of the relation of the different groups 
and the value of their characteiistics, is to be found in the fact that 
though his labours have been overlooked, all his genera, with a single 
exceptionj are to be found in recent systematic works, though under 
different names. Eaddi's * Memoir' was read in 1817, but it could 
not have reached London when Gray was passing the sheets of his 
work through the press, for the preface to the volume of the Transac- 
tions in which it is published is dated 10 Oct. 1820. Eaddi's names, 
under 
!hm 
'ound 
and the very opposition was useful to me by causing me to pay more attention 
to analytical studies, and to carry into zoology the knowledge, accurate termi- 
nology, and systematic method of study employed in the sister science, wliich 
has led me to believe that the study of botany is the best introduction, even 
now, for the successful prosecution of the other branches of natm-al science." 
