CHAETOPHORA. 115 



STIGEOCLONIUM LONGIPILUS, Kg. 



Bright vegetative green, mucous, pulviuate, 2-10 mm long, 

 stems simple until near the end, then fasciculately branched ; 

 all or nearly all the apices prolonged into hyaline setae. 

 Diameter of the stems 11-14 yw ; length of articulations 1-2 

 diameters. My specimens have the basal cells about six 

 times as long as wide. 



Syn. Myxonema drapernaldioides, Eab. ; Chaetophora draparnal- 

 dioides, Kg. 



There are two distinct forms of this species, the one 8-10 

 mm long, represented Plate Oil, figs. 1, 2, 3, with long bare 

 stems and bushy tops. Kirchner remarks that this species 

 may represent a transition state, going over to Chaetophora. 

 Personal observations prove the reverse, Chaetophora devel- 

 oping Stigeoclonium. 



The other form, as described by Rabenhorst, only 2 mm 

 long, represented Plate C, figs. 2, 3, forms a bright green 

 coating on stones in mill-races, often not 1 mm high. 



Plate CII, figs. 5-9, are very much elongated filaments 

 of Chaetophora, evidently going over to or developing Stigeo- 

 clonium. 



STIGEOCLONIUM RADIANS, Kg. 



Dwarf parasitic plant ; about 2 mm in length, filaments 

 radiate in small clusters, sparsely branched ; branches short, 

 tapering, pilose, involved in a somewhat firm mucus ; inter- 

 mixed with Chaetophora ; basal part of stems, 11-14 //, 

 articulations between 1 and 2 diameters long. Sometimes 

 constricted at joints. This form is also evidently related to 

 Chaetophora. Compare St. fastigiatum and St. Longipilus. 

 Parasitic on Avater plants. 



Plate CII, fig. 4, a small cluster. 



Genus 18, CHAETOPHORA, Schrank. 



Plants involved in a firm, gelatinous, coriaceous or hard mass, 

 of a globose or semiglobose, or plane, expanded, variously 

 lobed, form. 



Plants filamentous, articulate, branched ; stems radiately dis- 

 posed, composed of elongated vegetative cells with light chloro- 

 phylous contents in bands or centrally concentrated, divided 

 upwards into numerous branchlets which are shortly articulated ; 

 the ultimate joints attenuated, sometimes ending in a chaeta, 

 (bristle). 



