CCIX.— THE WATER VIOLET. 
Hottonia palustris Linne. 
A S we have previously had occasion to remark, aquatic Flowering Plants are, in 
most if not in all cases, descended from a terrestrial ancestry. Although there 
are genera and Families and even a few Orders made up entirely of aquatics, they 
are very often isolated genera or species whose nearest living relatives are land plants. 
Th is is, of course, the case with the Water Violet ( Holtonia palustris Linn£). In 
speaking of the Order to which it belongs we said that its members had in general 
simple, undivided leaves. The Water Violets, however, are in this respect 
exceptional : specially adapted to their surroundings, they have the finely divided 
leaves so general among submerged aquatic plants. Another vegetative character 
which they share with plants adapted to similar surroundings rather than with their 
near kin, is the formation of winter-buds or hibernacula which sink to the bottom 
during winter. On the other hand, the flower-stalk rising above water, and bearing 
flowers fitted for insect-pollination, is a clear indication of their terrestrial affinities. 
This small genus includes only two known species, one North American and the 
other our species, which ranges from western Siberia through Central Europe, not 
occurring in Turkey, Greece, Spain, or Portugal. Their generic name was given by 
the great Leyden physician Boerhaave (1668-1738) in honour of Peter Hotton, 
Professor of Botany there down to 1709. Both of them are floating herbaceous 
plants, with whorls of submerged leaves divided pinnately into many close-set, 
thread-like segments. The flowers are of a considerable size and are borne on a 
raceme of umbels, much like the inflorescence of Primula japonica Asa Gray, now 
familiar in our gardens. They vary in colour from white to pink or lilac, much as 
do those of the Lady’s Smock ( Cardamine pratensis Linne), secrete honey, and are 
dimorphic, like those of the Primroses. Cleistogene flowers are also occasionally 
produced. The calyx is divided into five almost to its base : the corolla is salver- 
shaped with a thickened throat and notched petals ; and the stamens are included 
within the corolla-tube. Sepals, petals, and stamens are occasionally six, seven, or 
eight, instead of five, in number. The ovary is globose and the style persists in 
the fruit stage, the capsule splitting into five valves which remain coherent both 
above and below. 
Our species ( Hottonia palustris Linn6) is generally distributed, though of 
somewhat local occurrence, throughout England and has been found in Ireland, but 
not in Scotland. It is a pale green, perennial plant, with a glabrous surface, with 
the exception of the pedicels and the peduncle in the neighbourhood of the flowers 
which are covered with glandular hairs. These serve probably, like those of Saxifraga 
tridactylites Linne, or the Catchflies ( Sileue and Lychnis), to keep off the small crawling 
insects that might steal the honey without pollinating the flower ; but it would be 
interesting to ascertain whether such insects may in this case be digested or otherwise 
