BOTANIC.-Ul. EXCHANGE CLUB. 
19 
hybrid forms of Rumex in England. The species which seem 
most prone to cross are R. pulcher, R. crisjnts, and R. congJomeratus. 
I have seen English specimens of apparently the following 
hybrids : — 
pulcher 
X rupestris. 
X obtusifolius. 
> > 
X conglomeratus . 
5 y 
X iiemorosus ? 
> > 
X crisjnis. 
crispus 
X obtusifolius (P. 2 ^ 1 'dt^nsis, M. & K.) 
y y 
X nemorosus. 
y y 
X domesticus (P. conspersus, Hartm.) 
conglomeratus 
X jnaritimus (Warrenii). 
y y 
X sglvestris. 
Of these R. pratensis [crispo-ubtiisifolius) is by far the most common. 
This is an exceedingly variable plant, showing a series of forms 
completely connecting its two supposed parents. Probably the 
plants are often again crossed by eitt^^^yispas or ohtusifolius , and 
secondary hybrids result ; it is convenient for further distinguish- 
ing these forms to call them crispo-j)ratensis or obtusifoUo-jyratensis. 
— H. Trimen, 28th February, 1879. 
Rumex maxivms. A supply this year from ditch-sides at Lewes, 
Sussex, J. H. Jennee ; Kelvedon, Essex, E. G. Varenne ; and St, 
Mary’s, Scilly (coll. W. Curnow), J. Bales. 
WulJJia arhiza. A good supply this year from a new station, 
a pond near the canal between Hanwell and Brentford, Middlesex, 
G. Nicholson. 
Potamogeton Zizii, C. & S. A plant sent by Mr. Brotherston 
from Cauldshiels Loch, near Melrose, Boxburgh shire, matches 
German specimens so labelled in the Kew herbarium by Dr. 
A. Braun. P. Zizii appears to be a large deep-water form of 
heterophgllus, simulating P. lucens in general habit, and destitute of 
floating leaves. The same plant is in Borrer’s herbarium from 
Llyn Maclog, in Anglesea, gathered by Wilson. 
Zannichdlia polgcarpa. Brackish ditch in the Peoples’ Park 
at Belfast, S. A. Stewart. An interesting addition to the Irish 
flora. 
Zostera angustifolia. Dr. Trimen points out that a plant 
gathered by Mr. Waterfall at Plymouth, and labelled Z. nana, is 
properly angustifolia, and that the true nana, of which Mr. Balfs 
has sent a good supply from Cornwall, may be readily distin- 
guished in the absence of flowers by its strictly 1-nerved leaves. 
Naias flexilis. A supply sent this year by Mr. Stewart and Dr. 
Boswell from the Scotch station. 
Allium carinatum. Sandy banks of the Esk, above Musselburgh, 
in large quantity, A. Craig- Christie. 
“ Iris Pseudo-Acorus, Boreau, Flore du Centre de la France. 
(Z. Pseudacorus, Linn., var. genuina, Syme Eng. Bot.) Banks of 
Thames, Kew, Surrey, and fish-pond, Sion House, Isle- 
woi-th, Middlesex. This is a very distinct Iris, and easily 
distinguished from the prevailing form (I. acoriformis, Boreau, 
