I9I4- RIDDEI.SDEI.L. — The British Forms of Helosciadium. 95 
THE BRITISH FORMS OF HELOSCIADIUM. 
BY THE REV. H. J. RIDDELSDELL. 
[Largely based on a paper read before the Cotteswold Club, at Glouces- 
ter, 17th March, 1914, from which the quotations, below unacknowledged, 
are taken.] 
Since writing a paper on Helosciadium forms, in con- 
junction with Mr. E. G. Baker, for the Journal of Botany 
(1906, p. 185), I have devoted a good deal of time to the 
genus. At the present moment, as a large number of 
specimens are at my disposal, through the kindness of 
Messrs. Bailey, Hanbury, Praeger, Druce, and other botanists, 
it seems opportune to put together and make public some 
of the conclusions to which my further studies, in the 
field and in the herbarium, point. The conclusions are, 
some of them, final, some tentative : some of them must be 
tested by cultivation of forms, especially in the case of H. 
nodifloYum and H. repens. What is here said can there- 
fore, in some cases, be only regarded as a stage on the 
way to further investigation : but all of it seems likely to 
have a value in that direction, and it is better therefore to 
publish it as a whole. 
H. NODIFLORUM, Koch. 
I. Habitat : varies greatly, within certain limits. " It 
is always a plant of watery places, though its foliage and 
inflorescence are almost always raised above the surface 
of the water." Its most characteristic spot is some 
deepish, rather shaded ditch, which normally has some 
small depth of water : but almost any fresh-watery spot 
will do ; " rough, swampy ground, either shaded or occupied 
by a good deal of varied low -growing vegetation ; muddy 
margins of ponds ; parts of grassy or heathy hillsides, 
which are wet in winter and dry in summer ; the damper 
parts of the fiat, sandy ground behind dunes, which com- 
pletely dry up in summer, though they are under water 
at other seasons. Its roots are probably always within 
easy reach of water." It thrives in competition with other 
species. 
