STAURASTRUM. 









221 



It should also bo compared with St. 



(Trop. u. subtrop. Sum. Thlor. 1899, p 



Tiew 



30, t. 2, f. 45), from which it differs ia the verrucation of the semioell. and in the nature and 

 direction of the processes. In St. lepidum the margins of the process are denticulate in front 

 and smooth m the vertical view, whereas in St. subindentatum the processes are nodulose, each nodulation 

 being equally developed all round the process. On the apices of St. lepidum are four prominent 



teeth forming the corners of an 



conspicuous at the sides of the vertical vie 



but in St. subindentatum there are no corresponding teeth on the elevated apex. 



153. Staurastrum compsobrachiatuy sp. n. (PI. xv., figs. 23, 24). 



St. subparvum, circiter lj-plo latius quam Ionium, modice constrictum; wmioellnia 

 campanulatse angustae sed inflatse ad basin, parte superiori murgimim latcralum lata 

 divergenti, apice convexo, angulis superioribus in processus loniros et gnrite rteurvatos 

 (primum horizontal iter dispositos, turn valde incurvatos apice extrorsutn curvato) pro- 

 duces, marginibus proceesuum minute crenulatis, apicibus pr< ossuum minute Irispinatit, 

 cum denticulis minutis ad basia processuum (plerumquo donticulii 2 inforne ct un<> 

 superne); a vertice visse ellipticse, polis in processus longos productis, t union' magno 

 truncato ad medium utrobique, margiuibus processuum minus crenulatis et apicibus 

 unispinatis (ut visis) ; membrana glabra. 



Long 35-36/*; lat. cum proc. 50-57'5/a; lat. isthm 4-2-*>*6> ; lat. lias, semioell. 

 7*2-9/*; cross. 13/*. 



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



This pretty little Staurastrum was observed in abundance, and does not appear to be .lowly 

 allied to any other species. It is readily distinguished by the graoeful curvature <-f the processes 

 ■which are at first horizontal, then strongly incurved with the apices turned outwards. The margins of 

 each process are minutely crenulate, and the apex is furnished with a pair of small ppines asymmetri- 

 cally disposed. The small denticulations, above and below, at the bases of the processes, were 

 present on all the specimens examined. The large truncate protuberances in the middle of the 

 upper part of semicells are also very characteristic. 



154. Staurastrum gracile Haifa, Brit. Desm. 1848, p. 136, t. 22. f. 12. 



Var. verrhoosum W. & G. S. West, Alg. Madag. 1895, p. 77, t. 9, f. 1. 

 Lat. cum. proc. 80 /*. 

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



155. Staurastrum Sonthalianum Turn. Freslm. Alg. E. India, 1893. p. 124, 





14, f. 27 





Forma ad basin semicellularum glabra (sine verrucis). 

 Long. 39,; lat. cum proc. 61-69,.; isthm. 12-5, ( P). xvi, fig. 

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



Turner figures the presses in the vertical riew with smooth margm., 



hut we do not find this 



to be 



156 



Staurastrum Sebaldi Beinsch, 1867; Algenfl. Frank. 1867, p. 175, t 



f . 1 



Forma orientalis 



arum undulatit 



Forma minor, marginibus inferioribus sennceliu 



Long. 45,; .at. cum proc. 53-56,; lat. isthm. 17, (PI. m, *•) 

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



