154 



MUSCINE.-E 



In their organs of reproduction, and especially in the structure of the 

 sporogone, the Sphagnaceae exhibit some divergences from the typical 

 mosses. Some species are dioecious, and the ' flowers ' of the moncecious 

 species are never hermaphrodite, the male and female organs being always 

 distributed on different branches. The male branches are distinguished 

 by their densely crowded leaves, which are often of a bright red colour, 

 giving a catkin-like appearance to the branch. On removing these the 



antherids are found near the 

 middle of the branch. They 

 are minute nearly globular 

 or elliptical bodies, elevated 

 on a slender stalk, and 

 dehiscing by longitudinal 

 fission into valves. The an- 

 therozoids are spiral bodies 

 with many coils, and two 

 large flagellate cilia at the 

 posterior end. The arche- 

 gones are formed towards 

 ^lyt the extremity of the female 

 • branches, are accompanied 

 by paraphyses, and are 

 enveloped by perichaetial 

 leaves. They resemble in 

 all essential points those of 

 other mosses. On impreg- 

 nation the oosperm divides 

 by a horizontal septum into 

 two cells, the sporogone ori- 

 ginating from the upper cell 

 only. The nearly spherical 

 usually bright red sporange 

 differs from that of other 

 mosses in being completely 

 enclosed within the venter almost till maturity. It is, in most species, 

 elevated on a long slender pedicel, the pseudopode, which must not 

 be confounded morphologically with the seta of other mosses, being a 

 prolongation of the axis below the vagine. The lower portion of the 

 sporogone is widened out into a broad disc-like foot, resembling in 

 appearance the apophyse of Polytrichace^e, which is seated on the top of 

 the pseudopode, and enclosed in the vagine. The calypter, when finally 

 ruptured, is not elevated in the form of a cap, but remains attached as a 



Fig. 129. — 5'. acjitifoliuni. a, antheridial branches ; b, 

 leaves of primary' siem ; ch, perichaetial leaves with 

 sporogones(x 5). (After Schimper.) 



