206 



FRESH -WATER ALGiE FROM BURMA. 



101. Cosmarium tracrtdermum W. & G. S. West, Alg. Madag. 1895, p. 64, 



t. 6, f. 26. 



Var. ellipticum var. n. (PI. xv, fig. 18). 



Var. semicellulis subellipticis, apicibus convexis. 

 Long. 52/* ; lat. 38-40/*; lat. isthm. 19/* ; crass. 25/*. 

 Bab. — In springs on the river bank, Bhamo (No. 21501). 



102. Cosmarium reniforme (Ralfs) Arch, in Journ. Bot. 1874, p. 92. 

 Hab. — In springs on the river bank, Bhamo (No. 21501). 



103. Cosmarium latum Br£b. Liste Desm. 1856, p. 128, t. 1, f. 10 ; Roy & 



Biss. Scott. Desm. 1894, t. 2, f. 10. 



g- 



Celluhe lj-plo longiores quam latae; semicellulse rectangulares, angulis inferioribus 

 rotundatis et angulis superioribus magis rotundatis, apice levissime retuso in medio; 

 granulis subparvis, depressis ; a vertice visa? oblongae, polis rotundatis. 



Long. 68/*; lat. 54/*; lat. isthm. 18/*; crass. 29'5/*. 



Hab. — In a small pool, Kyaukse (No. 22192). 



The form seen -was rather more rectangular than the general shape of C. latum, and the 

 granules were slightly smaller and more numerous. But for its relative proportions it might almost 

 have been placed under C. quadrum Lund. The granulation was very similar to that of C. sublatum 

 Nordst., but there wore no punctulations between the granules. C. quadrum Lund., C. latum Breb., 

 C. sublatum Nordst., C. orthopUuruni Roy & Biss., G. margaritatum (Lund.) Roy & Biss., and 

 C. conspersum Ralfs are all species which require further investigation. 



104. Cosmarium multiordinatum W. & G. S. West, Welw. Afric. Freshw. Al 



1897, p. 121, t. 367, f. 1. 



Var. Burmensb var. n. (PI. xv, fig. 19). 



Var. angulis superioribus semicelmfarum leviter rotundatioribus, granulis paullo 

 majoribua et ad margines conicis. * 



Long. 77-83/*; lat. 59*5-64/*; lat. isthm. 19/*; crass. 41/*. 

 Hab.— Mansang, near Hsipaw (No. 24193). 



This variety differs chiefly in the somewhat larger size and conical form of the granules. 

 The conical granules are principally evident round the margins of the semicells, the granules in 

 the centre being more rounded. The scrobioulations between the granules are small rounded pits, 

 and under no conditions of focus do they exhibit any angularity. 



105. Cosmarium subdecoratum W. & G. S. West, Desm. Singapore, 1897, p. 



loo, t. 8, f. 13. 

 Long. 60-64/*; lat. 50-52/*; lat. isthm. 16-17**; crass. 28/*. 

 Hab.— In the Kan-gyi at Mudon (No. 24505). 



106. Cosmarium bi*um Nordst. in Wittr. & Nordst. Alg. Exsic. 1880, No. 383; 



et m fasc. 21, 1889, p. 39. 



Var. crenis lateralis 7-9, crenis apicalibus 4-6, tumore sapra iathmum 



Z,lTr Tert ; CaUbuS , 5 " 7 Pwtarum circ. 8, et infeme cum aerie 

 Horizontal* singula granulorum 5-6. 



