384 NEW PUBLICATIONS. 
monographed the Silesian species in a valuable paper, translated by 
Henfrey in the first volume of his ‘ Botanical Gazette;’ with Krause he 
has published two extensive Herbaria of. European Salices, and now 
he gives the result of his long acquaintance with them in the volume 
before us. 
It is fortunate that those genera from the examination of which 
most botanists shrink, are the favourite study of some individuals. 
Hieracium is the delight of Backhouse in Britain, and Schultz-Bipon- 
tinus on the Continent. Babington is in love with Rudus, and there 
are in Germany some equally ardent admirers of that generally hated 
genus. Baker takes Rosa under his especial care, and Déséglise is an 
active confrère across the Channel. Borrer was deeply learned in the 
Salices, and Wimmer has studied them during a long life. As long 
as botanists generally are disinclined to deal with such genera, it is to 
be hoped that there will always be individuals who, having devoted 
themselves to their exposition, will find sufficient charms to induce 
them to prosecute their labours. 
The genus Salir presents peculiar difficulties to attaining a correct 
knowledge of it. ‘The unmeaning names of authors, their imperfect 
descriptions and figures, their slight and inaccurate characters, and the 
vast number of species; their numerous and nameless varieties, and 
the different phases belonging to the different sexes of each species, 
conspire to render it the most difficult and inexplicable genus in the - 
vegetable system." So wrote Dr. Walker, Professor of. Natural His- 
tory in Edinburgh University, seventy years since; in almost similar 
terms did Mr. Borrer express himself some years ago, after his study 
of the genus, and equally true are those words at the present day. 
Dr. Walker, one of the most philosophie naturalists of his day, the master 
of Robert Brown and of Jameson, studied this genus. His literary 
executors, some years after his death, published a volume of * Essays 
on Natural History,' which contained part of a complete review of the 
genus. As far as it goes, it is a model monograph, but unfortunately 
the remainder, which was promised in a subsequent volume, was never 
published. Notwithstanding the careful and precise specific diagnoses, 
the essay has, we may say, been entirely overlooked. It deserves to 
oe remembered, and we trust that future students of the genus will 
not forget Dr. Walker’s ‘Salicetum.’ We should like to know the 
synonymy of some of the species he there describes. 
