Literature 399 



The genus (Edocladinm, of which there is only one known species, (Edo- 

 cladium protonema Stahl ('91), is a subaerial Alga forming a stratum on 

 damp ground. There is a creeping portion of the thallus, firmly fastened to 

 the substratum by means of numerous colourless rhizoids. Standing up 

 from the creeping part of the thallus are erect branches, which are themselves 

 branched (fig. 253 A). The cell division is like that of (Edogonium, but 

 growth in length of the branches is mostly the result of the activity of the 

 apical cell. The latter has a conical cap, but is not piliferous. The zoogonidia 

 have the typical circlet of cilia. The plants are monoecious and the oogonia 

 are globose. Propagation may occur by resting ' cysts ' of one or several cells 

 formed on the underground rhizoids. 



Family OEdogoniacese. 



This is the only family of the CEdogoniales. 



The genera are: Bulbochxte Agardh, 1817; (Edogonium Link, 1820; (Edocladium 

 Stahl, 1891. The family was first monographed by Wittrock ('74) arid more recently on a 

 more elaborate scale by Him ('00). Bulbochsete only occurs in the comparatively still 

 waters of pools and lakes or in quiet bog-pools. It is less abundant than (Edogonium, 

 species of which are found in both still and running water. There are about 240 known 

 species of (Edogonium, almost all of which are recognized by the characters of the sexual 

 organs. Rather less than half the species are dioecious nannandrous and most of the 

 rernahider are monoecious. In the smaller genus Bulbochs&te most of the species are 

 dioecious nannandrous and the rest monoecious. In the latter the antheridia may be 

 either erect or patent. 



In the genus (Edogonium there is considerable range in size, the smallest species, 

 (E. angustissimum W. & G. S. West, having filaments only 2/i in thickness, whereas those 

 of (E. fabulosum Him attain a diameter of 85/x. 



LITERATURE CITED 



BLACKMAN, F. F. & TANSLEY, A. G. ('02). A Revision of the Classification of the Green 



Alg*. New Phytologist, 1902. 

 BRAUN, A. ('49). Betrachtungen iiber die Erscheinung der Verjungung in der Natur. 



1849-50. 

 FRITSCH, F. E. ('02 A). Algo logical Notes. II. The Germination of the Zoospores in 



Oedogonium. Ann. Bot. xvi, June, 1902. 

 FRITSCH, F. E. ('02 B). The Structure and Development of the young plants in GCdogo- 



nium. Ann. Bot. xvi, Sept. 1902. 

 FRITSCH, F. E. ('04). Some points in the structure of a young GMogoniurn. Ann. Bot. 



xviii, Oct. 1904. 

 HIRN, K. E. ('00). Monographic und Iconographie der CEdogoniaceen. Acta Soc. Sci. 



Fennicae, xxvii, no. 1, 1900. 



