64 
Ohio Naturalist. 
[Vol. 1, No. 4 
and published by Dr. A. J. Grout, of the Boys’ High School, Brook- 
lyn, New York, called “Mosses with a Hand-Lens.” The author 
says that many years of study of Mosses in the field and in Herbaria 
have convinced him that “any person of average intelligence can 
■easily learn to recognize seventy to one hundred common mosses, 
with the aid of a hand-lens of ten to fifteen diameters magnifying 
power.” 
I have Dr. Grout’s permission to reproduce two illustrations, 
which represent fairly that phase of his valuable book. Figure 9 
shows Ceratodon purpureus L , 
and the text pertaining to the 
same is as follows : “ Ceratodon 
is one of the commonest of all 
•our mosses. It is found on the 
•edges of paths, roofs of old 
buildings, sand by the seashore, 
and in general any barren com- 
pact soil is its favorite habitat. 
The plants are short and grow 
close together, forming dense 
thin mats of dark green. The 
lance-like young sporophytes 
appear early in spring as soon 
as the snow is melted. By the 
middle of summer the capsules 
often decay beyond recognition, 
and the seta breaks from the plant at the touch. 
Unless one has become very familiar with Ceratodon it is not al- 
ways easy to recognize it without mature capsules. When the cap- 
sules have fully matured they shrink when dry and become furrow- 
ed. This peculiar furrowing, the dark rich color of the capsules, a 
color called purple by the older botanists, but which is really a very 
dark chestnut or red-brown, make it easy to recognize this species.” 
Plate II. shows the Hair-cap Mosses, Polytrichum, the largest of 
all our species. There are four common species all having square 
capsules which character distinguishes them from Pogonatums, the 
latter having cylindric capsules. “The Ohio Hair-cap without the 
sporophyte (seta and capsule, commonly called fruit) is not readily 
distinguished from the Common, as the leaves and general appear- 
ance are very similar. But with the sporophyte present, the dis- 
tinctions are clear. In figs, b and d (Plate II.) note that the capsule 
of the Common Hair-cap is almost cubical, that the lid has a very 
short beak, and that the capsule is entirely covered by the calyptra. 
The capsule of the Ohio Hair-cap (e) is elongated, slender with a 
tapering neck, and with a much longer beak to the lid. The lid and 
the calyptra of the Ohio Hair-cap fall early in June, very soon after 
the spores are ripe, and it is not a lways easy to find either in position, 
but if the calyptra be found, it will be seen to cover the upper portion 
of the capsule only. The Common Hair-cap, although occurring in 
woods, is most common in open fields; the Ohio Hair-cap being 
