Simplest Forms of Life. 227 



paler lateral (hollow?) spot, with a hyaline nimbus, and surrounded by 

 wide coat ; mostly accumulated into strata or little heaps. Propaga- 

 tion by means of zoospores." This is not the same as C. Grev. Prob- 

 ably gonidia of lichens.] 



The three remaining genera are not widely distributed. 



Sorastrum spinulosu/ti, Ng., lives in moor-water, Cxlastrum ciibi- 

 cum, and C. SphcB/'icum, Ng., in swamps and ditches. Stauroge- 

 nia rectangidaris, Ktz., in swamps. 



II. FAMILY. PALMELLE^. 

 Small, generally roundish cells, living single or in communities, 

 which increase by binary division, and only produce swarm-spores in 

 the last generation. 



Cells 2 or 4, connected by gelatinous, stalk-like 

 stolons, 

 roundish, in pairs, Mischococcus, Ng. 



oval, in pairs, Cosmocladium, Breb. 



Cells without stolons, in series in gelatinous layers, 

 division in only one direction, 

 cylindrical families, combined in series, HormospJwra, Breb. 



single, gelatinous layer branched, feathery 

 [fixed, cells in parallel gelatinous tubes 

 ranged longitudinally in frond, and sur- 

 rounded by common gelatinous envelope], Hydriiriis, Ag. 

 Cells combined in several rows, or not at all 



Division in 2 or 3 directions, in families with hya- 

 line bladder-like covering, 

 which later bursts ; 2-4 cells, Schizochlamis, A. Br. 



which does not burst ; 



bladders oval or kidney-shaped, cells kidney- 

 shaped 2-16 Nephrocytiutn, Ng. 

 bladders cylindrical, tube-shaped, Palmodactylon, Ng. 

 " pear-shaped, fixed, Apiocystis, Ng. 

 round, Glceocystis, Ng. 

 in families in unstratified gelatin, without outer 

 coat, 

 family like a hollow ball [cells united by very 



fine, dichotomous filaments], DictyosphcErium, Ng 



family massive, spherical, Glceococcus, A. Br. 



family filamentous, branching and reticu- 

 lated, Pabnodyction, Ktz. 

 family spread out flat, 



single layer, generally 4 cells in a 



square, Tetraspora, Lk. 



several layers, 



