IV, 



MUSCI. 



355 



The mode of reproduction of Equisetacece is similar to 

 tliat of Ferns. 



In Equisetum diffiisum, the commonest species of the 

 Indian mountains, very nearly related to a common Euro- 

 pean species (E. pahistre), the fertile or sporange-bearing 

 fronds are either simple or branched. 



In E. hyemale^ an unbranched species of Northern Europe, 

 tlie epidermis contains so much silica that bunches of the 

 stems are sold for polishing metal. 



4. Natural Order, Musci. — The Moss Family. 



Minute herbs with filiform or slender wiry stems, and 

 alternate usually spirally-arranged and imbricating leaves ; 

 destitute of vascular tissue. Fructification consisting of a 



Fig. 238. Hair-I^Ioss [Polytrichiun]. a seta bearing a sporange ; b sporange covered 

 by its calyptra ; c head of antheridia, forming the male inflorescence. 



stalked sporange, usually with a central axis containing mi- 

 croscopic double-coated spores of one kind, capable of 

 developing a thread-like branching filament, upon which 



A A 2 



