The Irish Natufalist. 
May, 
on the hill sides, and a second Juncus association in the lower grounds. 
The distribution of species of Juncus and the plants occurring with 
them is another example of survey work where systematists would find 
a relation between the species and the soil-conditions. Where the peat 
bog becomes ill-drained and wet, Calluna loses its dominant place and 
gives way to other plants better adapted to the conditions. The 
authors record three of these associations— Briophorum, Scirpus, and 
Racomitrium moors, -of which the two latter are new. The distinc- 
tion between the Briophorum and Scirpus moors does not appear to 
be strongly marked in this district, except in regard to abundance of 
cotton-grass in the one, and the Scirpus-sedge in the other. The authors 
are, however supported in their distinction of a Scirpus moor by some 
later observations made in the North-west of Scotland, and criticism 
which might be made ought to be reserved until greater areas of these 
inaccessible and difficult peat bogs have been surveyed. The Racomi- 
trium association occupies small areas near the .summits of the hill mass. 
The name is used to designate a somewhat mixed vegetation of Calluna, 
Briophorum, and Scirpus, which has one common feature, the abundance 
of the moss Racomitriiim lanuginostim. The association occupies bosses of 
peat with intervening wet hollows, and its characteristic appearance is 
shown by an excellent photograph It is an association which is probably 
not uncommon on summit peat-bogs, and we suspect that the recording 
of it has been overlooked by other workers. This paper has therefore 
added materially to our knowledge of the plants, which by their growth 
and decay have made most of our peat deposits, and it shows how much 
may be expected from future work on the vegetation of peat. Ireland? 
above all, offers such opportunities for observing plant life on peat-bogs, 
and for investigations on the historj^ of peat, that it is to be hoped that 
Messrs. Pethybridge and Praeger may not only be enabled to give more 
time to this work, but may also be supported by assistance from others. 
The investigation of peat bogs is slow and arduous work, hardly to be 
undertaken seriously in snatches of leisure. In the peat we have a record 
of the succession of recent plar.t growth on the earth, and so far as 
Britain is concerned, the work of reading the record has scarcely begun. 
The " Vegetation of the District South of Dublin" in many other ways 
opens out a new field for the out-door botanist in Ireland. The Royal 
Irish Academy are to be congratulated on the excellent way in which 
this paper has been illustrated. If our hearty appreciation of the work 
of the authors is not obvious, then this review has failed in its object. 
To one who has watched the various papers on botanical survey in 
Britain grow in the field and come into print, it is interesting to see how 
each one opens out new questions and improves on its predecessor ; this, 
the latest, has repeated history and stands as a model. 
W. G. Smith. 
The University, Leeds. 
