MOSSES WITH A HAND-LENS 



161 



METZGERIA. 



M. CONJUGATA Lindb. 

 is the only Metzgeria likely 

 to be found. It is appar- 

 ently not common but will 

 be easily recognized by its 

 narrow (gV inch) thallus 

 dichotomously branched,, 

 with very distinct midrib. 

 The capsules arise from 

 the underside of the thallus 

 and when open bear a tuft 

 of hairlike " elater bearers " 



FIGURE 86. Plants (mlTe, female and On the ti P f each f the 



gemmae-bearing) of Metzgeria furcata four valves. The perianths 

 (After Hooker.) The smallest plants , . ., . , 



are rather larger than natural size So are hispid, With a tiny tWO- 



far as the drawings go they represent 



lobed bract at the base. 



M. conjugate equally well except the plant I 



bearing gemmae. The drawing by Miss The Spores ripen in SUm- 



Thayer at the right shows the gemma: ATA, i 



along the sides of the thallus of M mer - A ne plants grow On 



conjugate! X 5- 



bases of trees and on rocks 



in damp cool places, most frequently in elevated regions. 



FIGURE 87. Pallavicinia 

 Lyellii (After Sullivant.) 

 Plant; part of thallus with 

 involucre, perianth and ca- 

 lyptra; part of perianth cut 

 away to show young calyp- 

 tra; capsule closed and 

 open; antheridium enclosed 

 in a leaf; elater and spores. 



in swampy places and on 



PALLAVICINIA. 



P. LYELLII S. F. Gray (Steetzia 

 of authors) has a flat creeping thallus, 

 l /4 to nearly ^ inch wide, sometimes 

 reaching four inches in length, with 

 margin somewhat sinuate, but not 

 lobed. The thallus is very thin, almost 

 transparent when dry, with a very con- 

 spicuous midrib and is simple, or not 

 more than twice branched in the larg- 

 est plants. The capsules are cylindric 

 with a fringed perianth surrounded 

 by short involucral bracts. The 

 spores are ripe in April. It is widely 

 distributed east of the Rocky Moun- 

 tains, but is probably more abundant 

 southwards ; growing among mosses 

 moist rocks and soil. 



