^8 . MESSKS. W. WEST AXD G. S. WEST ON 



70. CosMAEiUM Eegnellii, Wille, Bidrag til Sydanr. Algfl. p. 16, t. i. fig. 34. 



Tar. MADAGASCAHIENSE, nov. var. (PI. VI. fig. 39.) Var. angulis inferioribus minus 

 rectangularibus, sed lateribus plus divergentibus, sub apicibus levissime retusis, 

 apicibus levissime retusis vel rectis. 

 Long. 14-15 ^ ; lat. 14-17 [J^ ; lat. isthm. 3o-4|M/ ; crass. 6-7*5 [/j. 

 No. 3. 



The forms of this variety seem to connect the species to C. capittihim, Boy et Biss. 

 (Jap. Desm. in Journ. Bot. 1886, vol. xxv. p. 195, t. 268. f. 9). 



71. CosMAEiTJM GEOMETEicTJM, nov. sp. (PL VI. fig. 32.) C. minutissimum, tarn longum 



quam latum, profundissime constrictum, sinu lineari extrorsum ampliato; semi- 

 cellulse latissime truncato-pyramidatse, lateribus rectis et apicibus concavis, angulis 

 inferioribus acutis, angulis superioribus subapiculatis, in centro papilla prseditse ; 

 a vertice visa3 ellipticae, ad polos subapiculatse, papiM median A. utrobique instructoe ; 

 a latere visse globosae, in medio utrobique papilla prseditoe ; pyrenoidibus singulis. 



Long. 95-10'5/«<; lat. 9-5-10'5/u; lat. isthm. 2/i; crass. 6^. 



No. 3. 



72. CosMAnnjM SiNOSTEGOS, Schaar. Magyar. Desmid. p. 266, fig. 12. 



Var. OBTUsirs, Gutw. Materyaly do Plory Glonow Galicyi, p. 26, tab. iii. fig. 13 ; 

 Diagnos. nonnull. algar. nov. Galicia in Nuova Notarisia, Apr. 5, 1892, p. 21. Tomia 

 minor, semicellulse a vertice visse acutius quam in forma typica papillatse. 



Long. 9-10-8 /ii; lat. 11-11-5^1; lat. isthm. 3-6 ju; crass. 7*2 /u. (PL VI. fig. 33.) 



No. 1. 



73. CosMARirM EMARGixATUM, nov. sp. (PL VIII. fig. 14.) 0. minutissimum, paullo 

 longius quam latum, modice constrictum, sinu aperto subrectangulari obtuso; 

 semicellulse subellipticse, ventre leviter convexse, dorso valde convexse et in medio 

 retusse ; a vertice visse ellipticse, medio utrobique leviter subtumidse ; a latere visic 

 subglobosse ; membrana glabra. 



Long. 8-9-5 iu; lat. 7-8^; lat. isthm. 4-4-4-8^; crass. 7*6-8-5 ^u. 

 Nos. and 1. 



74. CosMARirM MINIMUM, nov. sp. (PL VIII. fig. 10.) C. minutissimum, quadratum, 



paullo longius quam latum, modice constrictum, sinu sublineari ; semicellulsD 



transversim rectangulares, lateribus et apicibus subrectis, angulis levissime rotundatis ; 



a vertice visse ellipticse ; a latere visse subrotundatse, apice truncato ; membran^ 



glabra ; pyrenoidibus singulis. 

 Long. 8-4 ^i ; lat. 7-2 /n ; lat. isthm. 3 ^ ; crass. 4'7 a*. 

 No. 1. 

 This is one of the least Cosmarla yet described, and has a characteristic form. 



