528 Siplionecc, HydrogarftracocC, Botrydiuin. 



vegetativa (h. e. proliferationibus globosis secedeutibus) tuai cellulis 



radicalibus (aplauosporis). 



Generatio zoogonidiis (isogametis) biciliatis, copulatione zygotuni 

 (isospora) nova individua gorniinando pra^bens efficientibus. Individuo- 

 i'uni ita generatoruiu contentus in aplanosporas nuinero indeterini- 

 natas srepius dein transmutatus; aplanosporne in raicrozoogonidia co- 

 pulantia dein transmutatae. 



BOTRYDIUM Wallr. [1815] in Ann. bot. pag. 153 {Etym. botrydon 

 acervatim), Kirchn. Alg. Schles. p. 83, Rostaf. et Woron. Ueber 

 Hotrydium granulatum p. 15-10, Cooke Brit. Freshw. Alg. p. 112, 

 WoUo Freshw. Alg. U. S. p. 155, De-Toni e Levi Fl. Alg. Ven. III, 

 p. 93, Hansg. Prodr. p. 96, Ih/dyogastrum [1810] Desv. Fl. Angl. 

 p. 19 p. p.!, Rabenh. Fl. Eur, Algar. III, pag. 265, Rhizococcmn 

 Desmaz. in Aun. Scienc. Nat. Botan. ser. I. vol. XXII, pag. 217, 

 Protococcus sp. Kuetz , Vauclieria sp. auct., Tremella sp. Dillen. 

 et Huds., Coccochloris sp. Spreng., Ulva sp. auct., Linckia sp. 

 Web. — Pars thalli unicellularis e terra emergens vesiculosa, 

 acicula3 capitis magnitudine, apice rotundata, basi rhizoidibus plu- 

 ries ramosis, mollibus, hyalinis in terram penetrantibus instructa. 

 Multiplicatio inacro- et rnicro-zoogonidiis nec non cellularum divi- 

 sione vegetativa. Macrozoogonidia (asexualia) intra plantulas rna- 

 jores Isete virides, aqua udas numerosa orta, ovoideo-oblonga, 2- 

 4-granulis chlorophyllaceis instructa, polo hyalino, vix acurai- 

 iiato ciliura singulum, longura gerentia, post brevi motus periodum 

 iinmobilia, cilio evanido, membranam forraamque globosain in- 

 duentia, magnitudine accreta et in terra uda formam Protococci 

 botryoidis evolutione peracta sumentia; macrozoogonidia e con- 

 trario sub aqua in cystas merabranain duplicein suinentia transfor- 

 uiata. Siccitate perdurante, contentus viridis vesicula} in rainis rhi- 

 zomorphis hypogaais abit ibique celluhc numerosae (celluhe radica- 

 les) membrana propria obvoluta), sa^pe moniliformi-seriata) effor- 

 niantur. II;x) celluhe radicales (aplanospora)) dein tura zoogouidan- 

 gia hypoga^a tuin plantulas vegetativas tuin hypnosporangia era- 

 dicata sistere possunt. Proliferationes thalli dein radicantes et scpto 

 discrotie a cetero thallo secedunt novasque plantulas eniciunt. Fxsic- 

 catione nimis exstanto, thalli meinbrana contrahitur ut contentus 

 chlorophyllaceus in cellulas (aplanosporas) primo virides dein ru- 

 fo-aurantiacas dividitur. Aplanospora} ha) tam virides quara auran- 

 tiaca» sub aqua sub zoogonidangia transformantur et e contontu 



