Chaetophorese 



297 



in the young plants of the larger genera. The zoogonidia of Stigeoclonium 

 and Chietopliora often develop in masses, and in many instances the adult 

 thallus is really a colony of plants which have grown intermingled. 



Fig. 191. A, Bulbocoleon piliferum Pringsh. x 240. Only the bases of the bulbous bristles are 

 shown ; on the left is a zoogonidangiurn (zg). B, small portion of plant of Acrochsete repens 

 Pringsh. x 420. C, single plaut of Tltumniochsete Hubert Gay attached to filament of 

 Oscillatoria sp. x 700. (A and B, after Pringsheim ; C, after Gay.) 



The genera are : Chs-tophora Schrank, 1789 ; Draparnaldia Bory, 1808 ; Stigeoclonium 

 Kiitzing, 1843 1 [=My3Conema, Fries, 1825; and inclus. Iwanoffia Pascher, 1906]; 

 Acrochsete Pringsheim, 1862 ; Bulbocoleon Pringsheim, 1862 ; Chsetonema Nowakowski, 

 1876 ; Ph&ophila Hauck, 1876 ; Etidodonium Szymanski, 1878 ; Thamniochsete Gay, 

 1893 ; Pseudochsete W. & G. S. West, 1902 ; Fridaea Schmidle, 1905 ; Ectochtete (Huber) 

 Wille, 1909 ; Trichodiscus Welsford, 1912 ; Didymosporangium Lambert, 1912. 



As pointed out by Huber ('93), Endodonium is so closely related to Stigeoclonium as 



a cement. This he has also observed in young plants of (Edogonium and in Characium 

 Sieboldi. The present author has found this substance at the point of attachment of the young 

 plants of many Green Algae, notably in the genera Microspora, Chsetophora, Thamniochsete, 

 Characium, Tribonema, Characiopsis and others ; also in attached Flagellates such as 

 Colacium. 



1 Stigeoclonium was adopted as one of the 'genera conservanda' at the Brussels meeting of 

 the International Botanical Congress, 1910. Consult also Nordstedt in Botaniska Notiser, 1906, 

 p. 123. 



