216 



FKESH-WATER ALG^l FROM BURMA. 



Th 



species 



closely resembles St. submonticulosum Roy & Biss. (Jap. Desm. 1886, p 



t. 268, f. 7) in the 

 It differs in 



orrangement of its emarginate warts 



238, 



and in the form of the vertical view. 



the trapezoid semicells, the widest part of which is at the base, in the straighter 



the presence of two pairs of minute spines on each lateral 



sides of the narrower sinus, an 

 margin of the vertical view. 



The four warts forming 



chain across the dorsal part of the 



micells from angle to angle are bispinate in St submonticulosum, but they are only emarginate 



in St. Mamangense. 



Staurastrum Burkillii sp. n. (PI. xvi, fig. 3) 



136. 



St. magnum, rotundato-ellipticum, circiter lj-plo longius quam latum, profund 



constrictum, sinu valde 



lorem 



contracto ; semic 



perto (late ovato) apicem versus late conico ad partem 



elliptico-subsemicirculares, ventre convexo, margine 



eiteriori semici 



cum 



dulis dep 



7 



gulis basalibus 



in 



amillos 



deorsum productis 



a vertice visse triangulares 



rotund ato-< 



concavis, 



membrana dense scrobiculata et ad angulos subincrassata 



lateribus leviter 



aneulis latissime rotundatis in medio cum incisione profunda et ap 



Long 



Ilab. 



113/x 



lat. 96-99/*; 



lat. isthm. 36/* 



Mansang, near Hsipaw (No, 24193) 



P 



This handsome Staurastrum is r 

 125, t. 6, f, 41-43), 



elated to St. Zahlbruckneri Lutkem. 



Central 



1900, 



but is at once distinguished by its 



extraordinary sinus, the deeply cleft 

 angles, the undulate margin of its semicells, and the concave sides of the vertical view. Lutke- 

 mUller's speoies was described from the Ningpo Mountains in Central China, and a variety of it 



var. 



mamillatum— has been found in 



W 



G. 



West 



Koh 



1901, p. 94, t. 3, f. 35-37). 



This variety is principally distinguished by the bilobulate or 



bimam 



angles, and in a sense it stands intermediate between typical St. Zahlbruckneri and 



St. Burkillii. In the latter the angles of the semicells are still more deeply cleft, this feature 



being par 



evident in the vertical view, in which the broad angles possess a relatively 



deep median notch. 



It 



is 



however, the sinus, at first widely open and then partially closed, 



which gives the disting 



aspect to St. Burkillii. 



137. Staurastrum punctulatum Br6b. in Ralf's Brit. Desm. 1848, p. 130 



34, f. 10. 



Long. 28-32/*; lat. 23-26/*; lat. isthm. 9/*. 



B.ab. — In springs on the river bank at Bhamo (No. 21501). 



> 



t 



138 



dilatatum Ehrenb. Infus. 1838, p. 143, t. 10, f. 13 



Staurastrum 

 Brit. Desm. 1848, p. 133, t. 21, f. 8 



Ralfs 



Va 



obtusilobum De Not. Desm. Ital. 1867, p 



5 



O 



t. 4. f 



47 



Nordst 



I 



Freshw. Alg. N. Zeal. 1888, p. 41, t. 4, f. 19 

 U'bu.: lat. 25-27/4*. lat. isthm. 7'5/t. 



Long. 24-5/a; 



J/ai.^Momauk, east of Bhamo (No. 21551). 



139. Staurastrum retusum Turn. Freshw. Alg. E. India, 1893, p. 104, t. 13, 



f. 13. 



Var. punctulatom Eichl. & Gutw. Nonn. Spec. Alg. Nov. 1894, p 

 t. 5, f. 44. 



Long. 20/*; lat. 20/*; lat. 7'5/i (PI. xv, fig. 30-32). 

 Hab.— Mansang, near Hsipaw (No. 24191). 



174 



> 



