Characeae. 31 



Ramuli verticilloruiii inter se dissirailes, primarii majores, secun- 

 darii minores et simpliciores diiobus ordinibus, qiiorum alter 

 supra, alter infra majores instructi Heterophyllae. 



11. N. hyalina. 

 Coronula oogonii 'e cellularum verticillo pentamero unico constructa'. 



Caiilis corticatiis vel ecorticatus. Ramuli simplices. 



Chareae. 

 Oogonia e latere (pq. superiore) cellulae antheridium (in monoicis 

 conjanctis) vel bracteam (in monoicis sejimctis et dioecis) susti- 



nentis nata IL Chara. 



Stipulodia in serie unica Haplostephanae. 



Stipulodia ramulonini numerum aequantia. 



12. C. Braunn 

 Stipulodia ramulo cuique duo. 



Dioica, planta magna, canlis diametro er. 1 • 3 mm. 



13. C. Hornemannii. 

 Monoica, planta tenuis, caulis diametro er. -3 mm. 



14. C. Hydropüys. 

 Stipulodia in seriebus duabus . . . Diplostephaiiae. 



Antheridia et oogonia ad ramulorum nodos diversos sita. 



15. C. sejuncta. 

 Antheridia et oogonia ad ramulorum nodos eosdem sita. 



16. (.'. zeylanica. 



I. Nitella Agardh. 



l. Nitella occideiitalis Allen in Bull. Torrey Bot. Glüh vol. XXI 

 (1894) p. 166 t. 187. 



Statura parva. Caulis tenuis. Ramuli verticillorum 8, incurvati, 

 semel furcati. Radii secundarii 2 — 3, unicellulares acuminati. Oogonia 

 solitaria vel geminata, late ovoidea magna, cellulis spiralibus ad apiceni 

 maturitate turgidis. Coronula decidua. Oospora intenso castaneo- 

 brunea, circiter -4 mm. longa, -35 mm. lata, paulo complauata, 7 — 8 

 liras exhibens, membrana crassa leviter et irregulariter rugosa. Dioica. 

 [Plantam masculam ex Antill. nos nou vidimus.] 



Hab. in Cuba in Rio Saltadero: Linden (Herb. Eerol.). 



This was labelled by Braun "N. acuminata v. subglotnerata?'; but the 

 fruit resembles that of X. opaca ratlier than N. acuminata., and we liave 

 fonnd no traee of antheridia, aithough there are quite young oogonia, so that 

 we conclude that it is dioecious. Dr. Allen has deseribed four Nortli Ameriean 

 species of a group which he separates fiom N. opaca by the acuminate terminal 

 rays, viz. N. monlana., N. Blankinshvpii, N. missouriensis and X. oecidentali^. 

 LmoEN's plant is evidently closely related to theso and coraos nearest to 

 the last named, which was deseribed from California, and we have theret'jre 

 provisionally referred it to that species. We are however inclined to tliink 

 that all four of Allen's plants may have to be united iiito a sinyle species, 



