sitory flagellated condition. In morphology and taxonomic position 

 they correspond to the Rhizochloridales of the Xanthophyceae pre- 

 viously treated. Although some genera are colonial, most of them 

 in our region are unicellular, either with or without a lorica. 



There are 1 or 2 golden-brown chromatophores and the customary 

 food reserve is leucosin. Some forms are amoeboid in their food 

 habits. Only vegetative reproductive methods are known for this 

 order and resting cysts have been reported as occurring in but few 

 genera. 



FAMILY RHIZOCHRYSIDACEAE 



Characteristics as described for the order. (Pascher, 1927-1939, 

 recognizes separate families for several of the genera here grouped 

 in the Rhizochrysidaceae. ) 



Key to the Genera 



1. Colonial, 16 ovate cells radially arranged 



in a mucilaginous sheath Chrtjsostephanosphaera 



1. Solitary, or few cells adjoined by pseudopodia, 



not inclosed in a common mucilage 2 



2. Protoplast inclosed by a lorica of specific shape; solitary Lagynion 



2. Protoplast without a lorica; free-swimming 3 



3. Protoplasts adjoined by radiating pseudopodia to 



form an aggregate or complex of individuals Chrysidiastrum 



3. Protoplasts not adjoined by pseudopodia 



(or only temporarily and incidentally) 4 



4. Amoeboid cells with few, tapering pseudopodia Chrysamoeba 



4. Amoeboid cells with many slender needle-like pseudopodia Rhizochrysis 



CHRYSOSTEPHANOSPHAERA Scherffel 1911, p. 307 



Colonies of 2-16 ovate or subspherical cells, inclosed in a spherical 

 or disc-shaped mucilaginous sheath which is densely impregnated 

 with refractive granules of waste (?) material; the cells radiately 

 arranged within the mucilage and often showing several thread-like, 

 simple or branched pseudopodia; chromatophores 2 parietal plates; 

 2 contractile vacuoles (sometimes not clearly apparent); reproduc- 

 tion by cell division and by fragmentation of the colony. 



Chrysostephanosphaera globulifera Scherffel 1911, p. 307 



PI. 95, Fig. 41 



Characteristics as described for the genus; cells 10-12ju. in diam- 

 eter, arranged in a girdle within the periphery of the colonial 

 mucilage. 



In shallow water of bogs and acid swamps; intermingled with 

 other algae. Mich. 



[381] 



