Conjugatae, Zygnemacese, Mougeotla ^ll 



Zygnemem. Celluhc vegetativai cliloropliora sive tseniiBformia, margine irregu- 



lariter lacinulata, parietalia, recta vel spiraliter convoluta, sive asterifor- 



mia (bina) centralia foventes, mombrana sa^pius incrassata, mucosa, tegu- 



raento gelatinoso plus minus amplo haud raro involuta. 



Subfamilia prima Mesocarpeae De-Bary 



Mesocarpece De-Bary [1858] Unters. iib. Conjug. p. 70, Hansg. [1888] Prodr. 

 p. 149, De-Toni [1888] Consp. gea. Chloroph. in Notarisia III, n. 10 p. 453 

 ex parte. 



Thallus filiformis, e cellulis chloropliora laminaria, axilia, pyre- 

 noides plures includentia foventibus, membrana plerumque tenui, te- 

 gumento gelatinoso haud involuta pr£editis constitutus. 



Propagatio: 1. bipartitione cellularum vegetativa nec non fila- 

 mentorum fragmentis secedentibus. 2. Cystis. h. e. azygosporis seu aga- 

 mosporis (h. e. cellulis perdurantibns agamice ortis) habitu zygotis 

 similibus. 



Generatio zygotis e duorura aplanogametorum copuiatione ortis. 

 Zygota non e toto cellularum conjugatarum contentu efformata sed 

 septis 2-5 a 2-4 cellulis lateralibus (dein pereuntibus) discreta '). 



Conspectus generum 



Mougeotia. Zygota, genuina adsunt; zygota conjugatione binarum cellularum 



peracta, triquadripartitione cellulae conjugationis orta. 

 Gonatonema. Zygota nondum visa; aplanosporae sine conjugatione, (agamospo- 



rae seu azygosporae) cellularum singularum tripartitione ortse. 



MOUGEOTIA Ag. (1824] Syst. p. XXVI et 83 era. Wittr. [1878] On 

 the spore-forraation of the Mesocarpese (Etym. a cl. botanico gal- 

 lico A. Mougeot) Hansg. Prodr. p. 149 Cooke Brit. Freshw. Alg. 

 p. 99, Wolle Freshw. Alg. U. S. p. 227, Gay Ess. Monogr. Conjug. 

 p. 81, Kirchn. Alg. Schles. p. 127 Ripart Observations sur le Mou- 

 geotia genuflexa ser. V, tom. IX, 1868 p. 70-85 tab. VIII, Sphce- 

 rocarpus Hassall [1840?] in Ann. Nat. Hist. XI p. 434 et XII 

 p. 186 nec alior., Mesocarpus Hassall [1843] in Ann. Nat. Hist. XV, 

 p. 185 et [1845] Brit. Freshw. Alg. p. 166, Plagiospermum Cleve 

 [1868] Svenska Zygnem. p. 35. Sphcerospermum Cleve [1868] 



') Cfr. Wittroclc On the sporeforraation of the Mesocarpeae 1878 ubi zygo- 

 torum evolutio amplius describitur. 



