48 



Veit Brecher Wittrock. 



.phologically, not physiologically) rhizoid part, developed from 

 the germinated spore downwards, almost always sterile and 

 branchless, commonly unicellular. Spores neutral, quiescent 

 (agamo-hypnospores), generally cask-shaped, single, formed by 

 division into two of the caulold cells, of the chlorophyll-filled 

 and commonly widened upper parts of these cells; in germi- 

 nating as a rule dividing into two cells, the one giving rise 

 to the cauloid and the other to the rhizoid part of the thallus. 



[Pithojjhoracew nob. Algse (aquas dulcis) chlorophyllaceee, clado- 

 phoroideae, e seriebus cellularum bipartitione cellulas terminalis genitis 

 exstructas. Thallus a duabus partibus distinctis constitutus: l:o parte 

 cauloidea, e spora germinata sursum evoluta, propagativa, semper (fere) 

 ramosa, ramis e cellulis suffultoriis paullo infra apicem egredientibus ; 

 2:o parte (morphologice non physiologice) rhizoidea, e spora germinata 

 deorsum evoluta, semper fere sterili et simplici, plerumque unicellulari. 

 Sporas agameas, quiescentes (= agamo-hypnosporas), saspissime orculas- 

 formes, solitarias, bipartitione cellularum partis thalli cauloideas formate; 

 (cellulas singular, matres sporarum, parte superiore tumefacta et contento 

 chlorophyllaceo farcta, sporas singulas et cellulas singulas steriles sub- 

 sporales gignunt). Sporas germmantes in binas plerumque cellulas divisse, 

 cellula altera in partem thalli cauloideam, altera in partem thalli rhizoideam 

 denique evoluta.] 



GENUS PITIIOPHORA nob. 

 Character the same as that of the order. 



Sectio I. PITHOPHOILE ISOSPORE^: 



Spores all of the same principal form in each species; the in- 

 closed either cylindrical or cask-shaped, the terminal either C}dindrical 

 or cask-shaped with the upper end conical and the top somewhat rounded. 

 (Species 1 to 5). 



Species l. Pithophora sumatrana (v. Mart.) nob. 



Synon. Cladophora sumatrana v. Mart. Die Tange ; pag. 20, pi. 2, fig. 2. 



Diagnosis : Principal filament of the cauloid part of the thallus in 

 fertile specimens on an average 127 p 1 ) thick, with branches only of the 



The numbers in the diagnoses are all average numbers, gained by com- 

 parison of a great number of measurements. 



