252 
The Bouche d' Erquy in 1907. 
another point, viz., the relative ineffectiveness of the annual 
Salicornia lierbacen in this type of marsh-building. For these 
plants have no lateral extension nor do they recur from year to year 
at the same spots. The hummocks which they attach are very 
small. 
Hummock-complexes originating in the way described may 
remain as such, or more frequently, Salicornia lierbacen settles in 
the depressions between, developing in some cases into apple-green 
channels, whilst in others, probably where the soil is less permeable, 
the hummocks appear to be gradually embedded, so that the ground 
is levelled up. The details of these further stages of development 
have not, how T ever, been fully worked out as yet. 
Of the mode of origin of the very characteristic red Salicornia- 
flats or “crimson plains” there are no data available, as undoubted 
developmental stages have not been detected. It is possible, no 
doubt, that the zones of Salicornia raniosissinia (described on 
p. 250) represent an early phase of this association, but it is 
premature to venture on a definite opinion. 
Other Work. 
In connection with the developmental studies outlined above, 
a beginning was made, by the Chemical Section, of an investigation 
into the nature of the progressive changes which the soils undergo 
in the successive phases of colonisation. The bacteriology of the 
soils is also receiving attention. 
In the Physiological Section the work upon transpiration and 
osmotic pressure was continued. As regards the latter the young 
seedlings afford by far the most convenient material; and as both 
Salicornia and Suaxla can be readily grown in water-cultures it 
seems probable that this method will be the most useful one to 
adopt. 
For the first time since the inception of the work a photo¬ 
graphic specialist was able to devote his undivided energies to 
photographic studies on the marsh. A dark room w r as fitted up at 
the Laboratory by Dr. Somerville Hastings who developed more 
than a hundred negatives illustrating various branches of the 
investigation. Colour photography w*as represented by Dr. Kenneth 
Mees, and his results will be awaited with interest. 
As in former years the local population received us with every 
consideration and in a variety of ways gave evidence of the cordiality 
and kindliness of their feelings towards the party. 
F. W. OLIVER. 
R. MADLEY, Steam Printer, 151, Whitfield Street, Fitzroy Square, VV. 
