§2 ENGLISH BOTANY. 
local, but spreading over the country, being first noticed by Mr. John — 
New, at “ Waringstown, co. Down, about the year 1836.” The female 
plant alone is known to occur in Britain. 
(England), (Scotland), (Ireland). Perennial. Summer, Autumn, | 
Plant wholly submerged, the branches rising to the top at the time _ 
of flowering, the flowers resting on the water but not rising out of if, 
Stem slender, cylindrical, brittle, much branched, emitting roots 4 
the nodes. Whorls rather distant below, approximate towards th 
apex of the branches, mostly with 3 leaves on each, but sometimes 
with 4, the lowest nodes wits the leaves sometimes opposite. Leaves 
slightly amplexicaul, } to 3} inch long, variable in breadth, brigh 
green, translucent, with a thickened midrib, finely serrulate on th 
margins. Spathe axillary, from one or more of the whorls 
wards the extremity of the branches, clavate-cylindrical, split at th 
apex, membranous. Tube of the per ianth 2 to 8 inches long, filiform, 
Flowers about + inch across, pale lilac. Sepals concave. “Petals at 
length reflexed. Filaments strapshaped, without anthers. Stigmas 
papillose. The male plant or the fruit I have never seen, and even in. 
America it appears to be much less common than the female, whic 
there has the flowers with the stamens apparently perfect. 
Dr. Asa Gray says that the male flowers break off and float on th 
surface, as in V allisneria. 
When grown in an aquarium I have seen it with leaves as narroy 
as those of Callitriche autumnalis. 
Water-Thyme. 
The history of this curious water plant is very interesting, and has given rise t 
much discussion among botanists as to its introduction into this country. It is 
Anacharis Alsinastrum of the first and subsequent editions of Babington’s “ Manual of 
British Botany.”’ More recently it has been identified with a well-known North Ame 
can plant, and referred to the genus Plodia, by Mr. Bentham and others. We are in 
debted to Mr. W. Marshall, of Ely, for a very careful collection of facts bearing on the 
discovery of this plant, and its claim to be considered a British native, in four letters” 
published originally in the ‘“ Cambridge Independent Press,” and afterwards in the 
“ Phytologist’ of 1852. These letters were also published in a separate form, and 
through Mr. Marshall’s kindness we are able to avail ourselves of them full, 
This weed was first found in this country on the 3rd of August 1642, by Dr 
George Johnston, of Berwick-on-Tweed, in the Lake of Dunse Castle, in Berwick= 
shire. Specimens were sent to Mr. Babington, but the discovery was lost sigh 
of, and the interest died away until the autumn of 1847, when it was again disco= 
vered by a lady, Miss Kirby, of Market Harborough in Leicestershire. The plant 
were all females, and were closely matted together in great abundance. Miss Kirby 
had not observed it there before, and the reservoirs had been cleaned out 
years previously. Miss Kirby’s rediscovery awakened the attention of botanists t 
the subject, and Mr. Babington published a description of the plant in the “ Anns 
of Natural History” for February 1848, in which he advocates the notion 
Udora is a true native, and not, as is since pretty generally believed, an introd) 
