244 LAGERHEIM, BIDRAG TILL AMERIKAS DESMIDIÉ-FLORA. 



5. A, triaügularis nov. spec. tab. XXVII, fig. 22. 



A. medriocris, incisura mediana amplissima; semicellulae 

 istlimo cylindrico conjunctss subtriangulares, lateribus rectis 

 vel subrectis, dorso subrecto in medio retuso, angulis subacutis 

 Spina longa recta singula munitis; spinse parallelse vel pauUu- 

 lum convergentes; semicellulse a vertice visse lanceolato-ovales, 

 a latere subcirculares. Membrana liyalina, non punctata, in 

 medio non incrassata. 



Long, cell, 30 f.i; lat. cell. 25 ^t; long. ac. 25 /t; lat. isthm. 7 w. 



Cuba. 



Long. cell. 28 u; lat. cell. 28 j^i; long. ac. 24|t<; lat. isthm. 6 ^t. 



Georgia. 



6. A. pachycerus nov. spec. tab. XXVII, fig. 23. 



A. parvus, incisura mediana acutangula mox valde dila- 

 tata; semicellulffi subovales, lateribus leviter convexis, dorso 

 ro tun dato, angulis obtusis spina crassa recta vel subrecta 

 singula munitis; spinse divergentes; semicellulse a vertice visse 

 ovales; a latere visas subcirculares. Membrana glabra in medio 

 non incrassata. 



Long. cell. 20 i^i; lat. cell. 18 i.i; crass. cell. 10 j^t; long. ac. 10 u; 

 lat. istlim. 5 f^i. 



Cuba. 



Arten påminner något om Staurastrum franconicum Reinsch 



Algenfl. V. Frank, tab. XII, fig. III, f. g. 



7. A. octocornis Ehrenb. 

 Infus, pag. 152. 



F. Ralfs Brit. Desm. tab. XX, fig. 2 a— e. 



Long. cell. 24 u; lat. cell. 15 Jt/; long. ac. 18 /<; lat. istlim. 6 i.i. 



Georgia. 



Long. cell. 15 (.r, lat. cell. 18 i.i; long. ac. 12 ^tt; lat. isthm. 6 ,a. 



Tewksbury, Mass. 



Long. cell. 18 fx', lat. cell. 13 }.i; long. ac. 15//; lat. isthm. 5 ,«. 



Cuba. 



