1898] SOME NEW BOOKS 133 
occur in the district which comes in this position, 7.c., in the above 
case, the plant is absent in lowland Perth, Isla, and Forth, as well as 
in Gowrie. 
But in some cases there is also a short and much needed account 
of the less known varieties, eg., Trifolium dubiwm, Sibth. vay. 
pygmacum Soy.-Will. is described as follows, “ Dwarfer; petiole of 
middle leaflet not longer than the lateral ones.” These occasional 
deviations from the plan are probably the most valuable part of the 
book, and we wish there had been more of them. 
Mr F. J. Hanbury has edited the Hieracia, Mr H. Groves has 
worked through the Characeae, and Messrs W. Barclay and H. Coates 
have afforded Prof. Traill much assistance with those genera (Salix 
Festuca, ete.), which were not finished in the MS. Prof. Traill’s 
portion of the work must have been exceedingly difficult ; he has 
however succeeded in presenting Dr Buchanan White’s work in the 
best form possible under the circumstances, and deserves congratula- 
tion on the accomplishment. The map (by Bartholomew) is ver 
good, coloured according to altitudes of 500, 1000, 2000, and 3000 
feet ; but is on far too small a scale for detailed work in the field. 
THE FERNS OF THE EARTH 
Die FARNKRAUTER DER ErpDE. Beschreibende Darstellung der Geschlechter und 
wichtigeren Arten der Farnpflanzen mit besonderer Beriicksichtigung der exoti- 
schen. Von Dr H. Christ (Basel). 8vo, pp. xii+388, with 292 figures. Jena: 
Fischer, 1897. Price, 12 Marks. 
In this work Mr Fischer has added another useful book to his long 
list of botanical publications. Apart from their general life-history 
the modern botanist knows next to nothing about ferns, and is often 
fain to admit his ignorance of the names of the most commonly culti- 
‘vated species. He knows Péeris aquilina, the bracken fern, but is sur- 
prised to find that a fern which is used for decorative purposes, along 
with one or more equally unknown palms, in most of the London 
dairies, or in smaller editions as an ornament for the dinner table, 
is congeneric. He will find Dr Christ’s book very useful. It is not 
a complete monograph, for such a work would require several volumes 
of equal size to the one now before us, and it is therefore not intended 
primarily for the specialist, but notwithstanding includes descriptions 
of 1154 species belonging to 99 genera. If further information is 
required, it can be found in one or other of the systematic works 
of which the author gives a list at the beginning of his book, or of 
the floras which follow arranged in geographical sequence. Under 
the title ‘Ferns’ Dr Christ includes the so-called true Ferns or 
Filicinae of Prantl which fall into two groups, namely, the Lepto- 
sporangiatae, in which the spore-cases are derived from a single 
(epidermal) layer of cells, and the smaller or Eusporangiatae where 
several cell-layers are concerned. The first group contains the 
Hymenophyllaceae, Polypodiaceae, Davalliaceae, Osmundaceae, Cyath- 
eaceae (tree-ferns) and others, the second the two small families 
Marattiaceae and Ophioglossaceae. The first part of the book (15 
pages) is a brief systematic outline of the characters of the groups 
and genera. The remainder, forming Part IL. is a more exhaustive 
account of these and of the principal species, including all well-estab- 
lished species, “which are in any way remarkable on account of 
