LABORATORY STUDIES 253 
(c) Place a spore-case under the microscope and examine 
with a low power, noting the lid. Now remove the lid and 
observe the teeth. The teeth may be studied still better by 
splitting the spore-case from base to apex and then mounting 
in alcohol, and afterward adding potassium hydrate: or the 
lid may be removed and a transection of the spore-case made 
just below the peristome, so as to show the latter from above. 
In these specimens spores may be studied also. 
(d) Split a young spore-case and examine the external sur- 
face of the lower part for breathing-pores, and note internally 
the adjacent chlorophyll tissues, and the sporogenous layer 
above. 
(e) Collect a number of mosses not in fruit, showing at the 
apex of their stems little cup-shaped whorls of leaves. Make 
several vertical sections of one of these cups, and mount in 
water. Examine for antherids and archegones. Sperms may 
sometimes be seen with a high power. 
(f) The first stage (protonema) of a moss gametophyte may 
be found by scraping off some of the greenish growth from a wall 
or cliff or surface of a greenhouse flower pot where young mosses 
are just springing up. By mounting some of this in water and 
washing away the dirt the branching green growth may 
generally be seen, with here and there the buds which give rise 
to leafy stems. 
LITERATURE OF BRYOPHYTA 
D. H. CampsBe.., The Structure and Development of Mosses and 
Ferns, New York, 1905. ; 
L. M. UnpERwoop, Descriptive Catalogue of the North American 
Hepaticae, Champaign, 1883. 
L. LesqueREevux and T. P. James, Manual of the Mosses of 
North America, Boston, 1884. 
A. J. Grout, Mosses with a Hand Lens and Microscope, Brook- 
lyn, 1905-1911. 
