OF INDIA AND CEYLON. 
195 
has been laid on some of these variable characters. The 
Tristicheæ, to which Lawia and Tristicha belong, have a 
trimerons regular flower with perianth ; the depth of the 
segmentation of the latter is variable. The Eupodostemeæ, 
including the rest of the Asiatic forms, have a very 
zygomorphic flower, dimerous, without perianth. At the 
sides of the stalk of the monadelphous andrœceum there 
are two small thread-like organs, variously regarded as 
staminodes or as perianth ; these organs vary much in size 
and length. The length of the stamens also varies, and the 
number may be either one or two in the same species in 
several cases. The ovary characters are fairly constant, but 
the shape and size of the stigmas are very variable, 
especially in Hydrobryum. In many forms the cortex of 
the ovary is deciduous with that of the pedicel of the flower. 
The Fruit.—TliQ characters of the fruit are of great 
importance for classification in the order. The chief 
distinguishing points are the presence or absence of ribs, and 
the equality or inequality of the two lobes in the fruit of the 
Eupodostemeæ. When the lobes are equal, the ribs on each 
run down into the pedicel, and the fruit splits evenly down 
the central ribs into two lobes, both of which remain on the 
pedicel ; when the lobes are unequal, the ribs of one only 
are decurrent into the pedicel, and the other lobe falls ofP 
altogether after dehiscence. In the genera Hydrobryum 
and Farmeria, the characters of the fruit, which are usually 
generic, seem to be only of specific value. 
The fruits ripen after gathering, so that the length of 
pedicel, as already mentioned, is variable, and so also is the 
size of the fruit. The ovary being usually smooth the ribs 
are formed by the'Tall of the outer tissues of the wall and the 
lignification of the vascular bundles and tissue near them, and 
frequently (especially in specimens gathered unripe) these 
tissues do not fall away properly, so that the fruit is not so 
ribbed as usual, or may even be mistaken for a smooth 
fruit {cf, description of Mniopsis Johnsonii in Wight, I, c,~). 
