MOSSES WITH A HAND-LENS 



23 



THE URN MOSS 



THE Urn Moss is common on earth in conservatories, by road- 

 sides and in old fields. It is abundant in moist places by 

 paths in the parks of Greater New York. It must be col- 

 lected in May to get the calyptra in position. 



Although a very near 

 relative of the Cord Moss, 

 it entirely lacks the peri- 

 stome which is so con- 

 spicuous in that species. 

 A much rarer moss, 

 Pottia, may be found 

 and confused with the 

 Urn Moss, which it close- 

 ly resembles. Pottia, 

 however, is smaller, ma- 

 tures its capsules in win- 

 ter, and under a lens will 

 be seen to have the mid- 

 rib excurrent instead of 

 ending below the apex of 

 the leaf, as in the Urn 

 Moss. 



There are several spe- 

 cies of the Urn Moss, 

 but the one figured [Physcomitrium turbin&tutn (Mx.) Brid.] is 

 much the most common and most likely to be met with. 



Fig 1 

 capsule 



Physcomitrium turbinatum 



15- 



THE BRYUMS 



BRYUM is perhaps the most difficult and troublesome of all 

 the genera of mosses. The genus is large (500 species, 

 195 in Europe and America), and the distinctions between 

 the species are often few and difficult to observe. There are, how- 

 ever, two species that can be recognized readily by anybody. 



The Silvery Bryum ( />'. arginteum L.) grows everywhere at 

 almost all altitudes. It is specially fond of dry compact soil in 

 sandy fields and waste places. It grows abundantly in paths and 

 between the bricks of sidewalks in towns and cities. 



When fully grown it is a bright silvery gray, due to the fact 

 that the leaves are white and without chlorophyll when old. The 



