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 j)erson 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 Iiabitat. 

 The plants are short and grow 

 close together, forming dense 

 thin mats of dai'k 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 tlie 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, tlie 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 tlie 

 sporophyte (seta and capsule, commonly called fruit) is not readily 

 distinguished from the Common, as the leaves and general appeai*- 

 ance are very similar. But witii 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, tliat 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 

 tlie calyptra of the Ohio Hair-cap fall early in June, very soon after 

 the spores are ripe, and it is not always easy to find either in position, 

 but if the calyptra be found, it will be seen to cover the upper iiortion 

 of the capsule only. The Common Hair-cap, although occurring in 

 woods, is most common in open fields; the Ohio Hair-cap being 



Ceratodon. 



