22 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [BuU. 



lid to a distance of ten centimeters or more. The ripening 

 and scattering of the spores occurs in the summer months. 



THE ANDRE^ALES 



The present order contains the single genus Andreaea, 

 separated from the Bryales on account of the peculiar structure 

 of the capsule. The species are all small, and grow in tufts on 

 siliceous rocks, usually in mountainous regions. The gameto- 

 phyte consists of an upright and sparingly branched stem bear- 

 ing crowded leaves in the three-eighths arrangement. Except 

 for the midrib, which occurs in certain species only, the leaves 

 show no cell differentiation. 



The sporophyte bears a certain resemblance to that of 

 Sphagnum. It consists of an oval capsule and a well-developed 

 foot, but no true stalk is formed. The calyptra is very delicate 

 and is ruptured long before the spores are mature ; sometimes 

 it is carried up on the tip of the capsule, sometimes it remains 

 at the base and the capsule protrudes through it, very much as 

 in the Jungermanniaceae. The capsule contains a definite 

 columella, arched over by the spore cavity in the form of a 

 hollow cylinder, and is bounded on the outside by a wall 

 several cells thick. The wall has a distinct epidermis without 

 stomata, and is probably not very efficient as a photosynthetic 

 tissue, although some of its cells contain chloroplasts. When 

 the spores are mature, the tip of the archegonial branch elon- 

 gates rapidly, assuming the function of a stalk, and the wall 

 of the capsule splits along four longitudinal lines. These do 

 not extend, however, to the apex, but they are sufficient to 

 expose the spores and to allow them to be scattered by the 

 wind. Tlie capsule usually reaches maturity in the spring or 

 early summer. 



THE BRYALES 



The Bryales, or True Mosses, constitute the largest order 

 of the Bryophytes, and include about two thirds of the Con- 

 necticut species. The gametophyte varies greatly in size, being 

 sonu'times only one millimeter long and sometimes attaining 

 a length of ten centimeters or more. It always consists of a 

 leafy shoot, the leaves being usually arranged in more than 



