MR. W. JOSHUA ON BURMESE DESMIDIE^E. G49 



centro, saepe in serie externa modo visis. Longit. 44 fx, latit. 

 18 ii : isthmi latit. 15 fi. 



Medium size ; rather more than twice as long as wide ; nearly 

 cylindrical ; apex slightly truncate ; widely rounded at sides, in 

 middle slightly constricted, with rather wide angle ; side view of 

 semicells elliptical ; membrane crenate ; verruca? very faintly 

 visible, absent in centre of cells, the outer row only often the 

 only ones visible. Length 44 li ; breadth 18 li ; width of isthmus 

 15^. 



C. exasperatum, n. sp. (Plate XXY. figs. 1 & 2.) 

 O. parvum, fere tarn longum quain latum : cellulis anguste 

 ellipsoideis, profunde constrictis, angulolate hiante, prominentiis 

 validis, truncatis, irregularibus obtectis, in seriebus 2-3 horizon- 

 talibus in utraque semicellula dispositis : a vertice couspectis 

 angustis, ellipsoideis ; cytiodermate crasso. Longit. cum promi- 

 nentiis 40 ii, sine prominentiis 35 li : latit. cum prominentiis 42 ii, 

 sine prominentiis 38 \x : isthmi latit. 11 /i : crassit. sine prom. 

 16 n, cum prom. 23 li. 



Small ; about as long as wide ; cells narrowly elliptical, co- 

 vered with rows of strong, truncated, rather irregular protu- 

 berances, arranged in 2 or 3 horizontal rows in each semicell ; 

 deeply constricted, with wide gaping angle ; end view narrow, 

 elliptical; cytioderm thick. Length with protuberances 40 ll, 

 without protuberances 35 ll ; breadth with protuberances 42 li, 

 without protuberances 38 ll • width of isthmus 11 n ; thickness 

 without protuberances 1G /i, with protuberances 23 ii. 



C. bifarium, n. sp. (Plate XXV. figs. 5 & 6.) 

 C. parvum, paulo longius quam latum ; profunde constrictum, 

 angulo anguste lineari, semicellulis subovatis ; angulis rotundatis, 

 minute regulariter granulatis, prominentiis 5-6 magnis sphsericis 

 in seriebus duabus horizontalibus dispositis ; a vertice conspectis 

 eubsphaericis, utroque latere polari promineutiam rotundatam, 

 elongatam ferentibus. Crassit. sine papillis 15 fi, longit. 25 ii, 

 latit. 23 n : isthmi latit. 6 ll. 



Small ; rather longer than wide ; deeply constricted, with 

 narrow linear angle ; semicells subovate ; angles rounded, mi- 

 nutely and regularly granulate, with 5 or 6 large spherical protu- 

 berances in two horizontal rows ; end view subspherical, show- 

 ing on each side of polar end a rounded elongate protuberance. 



LOfJT. JOURX. — BOTAKT, TOL. XXL 3 C 



