148 
OF THE MOSSES AND THEIR ALLIES. 
The amphigastria are a kind of modified leaves in the 
Hepatic^, answering in some respects to the stipules of 
more perfect plants. Growing, as they do, on the lower 
surface of the stem, and being very minute, considerable 
trouble is involved in searching for them, as numerous 
stems have to be examined ; neither are they always pre- 
sent over the whole extent of the stem. The most likely 
parts are healthy young shoots, especially those that sup- 
port the reproductive organs. The eye, too, should be 
directed to the sides of the under-surface, rather than 
along the central axis. For the purpose of examination the 
amphigastrise may be shaved off with a thin and very 
sharp penknife, or the stem itself may be divided, as 
directed for the true leaves. The latter method has the 
advantage of securing the stipule from injury, and of giving 
a good insight into its mode of attachment. 
on opposite sides of the stem. In other and fewer instances they are 
attached to, or grow from, all sides of the stem. It is of rare occur- 
rence to find the leaves notched at the margin, hut this sometimes 
takes place. 
The cells, of which the leaves are composed, are roundish, or 
hexagonal, from pressure, and very variable in size. This also is a 
great assistance in the determination of species. . . . The cells 
of the ladder scale Moss (Alicularia scalaris), for instance, contain 
peculiar nucleate bodies of from two to four granules in a hne in 
each of the cells (fig. 2) ; those of the three- toothed scale Moss (Pla- 
giochila tridenticulata) fig. 3, and of the curled-leaved scale Moss 
(Jungermannia curvifolia), fig. 4, will illustrate some of the forms of 
leaf cells.’ (‘ British Hepaticse ; an Easy Guide to the Study of,’ by 
M. C. Cooke — a work which piay be consulted with advantage by the 
student. It is crowded with figures, and its exceedingly low price 
places it within every one’s reach.) — Ed. 
