86 



The plants are found in cool moist places in deep woods. Mature in 

 autumn. They are large and Mnium-Vike, often called the giant Bryutn. 

 They grow from stolons, the leaves are clustered at the top of the stem, 

 forming rosettes. The plants are deep gieen in color, and form large loose 

 mats. 

 Sphagnxjm. 



The Sphagmims or peat mosses are the large, light, almost white, green 

 mosses found in bogs or in stagnant water. The genus only can be de- 

 scribed, for the microscope is necessary for species determinations. The 

 capsules are globular. The leaves are ecostate, entire, acute, translucent. 

 The plants grow in compact masses. Mature in summer. 



TORTELLA. 



T. caespitosa. 



This species is usually found upon trees. The calyptra is cucullate. 

 The leaves are costate, entire, acuminate. The costa is mucronate, excur- 

 rent. Margin plane. Leaves linear lanceolate, spreading when moist, 

 spirally contorted when dry. Basal cells hyaline. Plants caespitose, 

 radiculose, of medium size. Yellow green. Mature in spring. 



T. tortuosa. 



This form is found upon stones. The leaves are linear lanceolate, 

 acuminate, spreading when moist. The costa is excurrent. Densely 

 imbricate in habit, with undulate leaves. Plants medium to large. 

 Mature in late summer. 



TORTUL.A.. 



T. muralis. 



Leaves oblong, obtuse, margin revolute. Costa yellow, excurrent to a 

 long hyaline point about J^ the length of the leaf. Cells papillose. Cap- 

 sule ovate-oblong, sub-cylindric. Seta purple. Operculum long beaked. 

 Tufts small, forming dense white-green cushions on stones and rocks. 

 Mature in spring. 

 Ulota. 



U. americana. 



This Ulota is always found on rocks. Calyptra hairy. Capsules erect 

 and symmetric, exserted. Leaves costate, entire, acuminate, lanceolate, 

 curly when dry. Capsule is striate with a long neck. Plants black-green. 

 Mature in spring. 

 U. crispa. 



This Ulota is to be found on trees. It agrees with the above form in 

 calyptra and capsule characters. The leaves are costate, entire, acute, 

 ovate, crispate when dry. Hyaline cells at base of leaf. Plants form dense 

 cushions. They are small, bright green. Mature in spring or early sum- 

 mer. 



Webera. 



W. sessilis. 



This is a unique, form growing close to the ground in dense mats. The 

 capsule is ventricose, immersed, surrounded by a tuft of hairs and almost 

 sessile on the gametophyte. The leaves are lanceolate-acuminate. Its 

 habitat is a soil bank in deep woods. Mature in summer. 



