ETJASTEIDIUM . 



199 



E. erosum Lund. var. attentuatum Turn. (Freshw. Alg. of E. India, 1193, t. 10. t 18, 21) 

 stands somewhat near to E. dubium var. tritum, but the apex is retuse and not incised. Moreom 

 the Burmese plants have not the characteristic vertical and side views of E. erottm. 





70. Euastrum Bhamense sp. n. (PI. xiv, fig. 



E. minutum, circiter lj-plo longius quam latum, profunde const rietuin, sinu 

 angusto-lineari ; semicellulaa truncato-pyramidat;r , lateribua subinv<:ulnriter 3-1-un- 

 dulatis et levissime conveyis, angulis basalibus leviter rotundatis vel -ubrectanguln- 

 ribus, angulis apicalibus subrectangularibus vel subobtusis, ipica trunaato-conveio 

 et leviter 4-undulato, cum incisura mediana parva ot subaperta a vcrtice vil» 

 ellipticse ; a latere visas elliptico-ovatse ; membrana glabra. 



Long. 22-23*5^; lat. 15-15*5'5/a; lat. apic. 10. V; lat. istbm. 4-8-5 >; craM. 9^. 



Hah. — In springs near the Irrawaddy, Bhamo (No. 21501). 



This small speoies differs from E. binale (Turp ) Khrenh. in its mors pyranii 



\VI 



undulate lateral margins and undulate apices. It has also a more promiwnt apioal not oh, and the 

 semicells are destitute of a central protuberance. It is nenreet to B. bin V vsr. mbkb&tutn W. A 

 G. S. West, but differs in its undula f e apex, its deeper apical notch, and in the absence of tns 

 protuberance from the centre of the semicells. 



It should also be compared with E. doliforme W. & G. 8. West ^orae Detm. U, S. 18&P 

 p. 289, t. 16, f. 12), from which it is distinguished by its smaller size, its undulate apex and 

 more rounded apical angles, as well as by the absence of fhe protuberance at the base of the 



semicells. 



71. Euastrum binale (Turp.) Ehrenb. ; W. & G. S. West, Brit. Desm. ii. 190 



p. 51, t. 38, f. 28, 29. 

 Hal.— In springs on the river bank, Bhamo (No. 21501). Between Thingan- 

 nyi-naung and Kawkareik, in the side-channel of a stream (No. 2448M). 



72. Euapteum dekticulatum (Kirchn.) Gay, Note Conj. du midi do France, 



1884, p. 336; W. & G. S. West, Brit. Desm. ii, 100., p. I ., t. 89, 



f. 1-4. 



Hab.-In the Kan-gyi at Mudon (No. 24505). Between Thingan-nyi-naung and 



Kawkareik, in the side-channel of a stream (No. 24483) 



73. Euastrum validom W. & G. S. West, Some N. Amer. Desm. 1896, p. 



245, t. 14, f. 32, 33. 

 Forma angulis inferioribus subrectangularibus, granulis intra angulos inferior* nulhs. 



Long. 26^; lat. 19/*; lat. isthm. 4«8^; crass. Ilji (PL sir, fig. *> 



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



This form resembles very much Cosmarium midzyrzecens, Eichi. & Gutw. (Nonn. speo. alg. no*. 

 1894 p S Ttl 9), but dtfers in the form of the a F x and in the absence of the m^n 

 protuberence in the vertical view. 



Euastridium gen. nov. 



incisura apicah; semicellulae a ironie y^ 



Cellulae iis 



lit a fronte visae; a 



vertice visce actinomorphicce, 8-lobata? 



Akh. Rot. Bot. Gard. Calcutta Vol. VI 



