No. II.] THE BRYOPHYTES OF CONNECTICUT. 1 7 



function of holding the plant more firmly in place, and are 

 confined to certain species and genera. 



The archegonia are borne at the apices of stems or of 

 special branches and stop their further elongation. The leaves 

 and underleaves which develop in the immediate vicinity of 

 the archegonia are more or less modified, and are designated 

 bracts and bracteoles respectively. Taken together they con- 

 stitute the involucre. This often surrounds the developing 

 sporophyte and helps protect it. In the majority of the genera, 

 however, the gametophyte develops a special protecting organ. 

 This usually consists of a hollow tube, open at the top and 

 enclosed by the involucre ; and, since this tube is theoretically 

 formed by the coalescence of modified leaves, it is called a 

 perianth, although it is not homologous with the perianth in 

 flowering plants. In a few cases the fertile branch takes on a 

 peculiar growth as the result of fertilization, and forms a 

 hollow cup around the sporophyte. This is known as a 

 perigyniiim, and may be either pendent or erect. In the latter 

 case the uppermost bracts and bracteoles are often carried up 

 on the outside. In very rare instances the young sporophyte 

 penetrates the tip of the fertile branch, which serves directly 

 as a protecting organ without undergoing marked modifica- 

 tions. Under these circumstances the calyptra itself often 

 fails to develop. 



The Jungermanniales are about nine times as numerous in 

 Connecticut as the Marchantiales. Less than one seventh of 

 the recorded species are Metzgeriacese, the others being all 

 Jungermanniacese. A few are more or less aquatic, either 

 floating on the surface of the water or attached to submerged 

 rocks or stones. A few others are to be found in bogs or 

 swamps. The remainder grow on rocks, on banks, on earth, 

 or on the trunks of trees, usually in damp and shaded localities. 

 They vary greatly in size, a few being hardly perceptible to 

 the naked eye, while others attain a length of ten centimeters 

 or more. The sporophytes, with few exceptions, reach 

 maturity in the spring. 



