THE FRESHWATER ALGZ OF CEYLON. 149 
This variety differs from Zuastrum intermedium, var. purum, West & G. S. West, in its 
less open sinus, its subtruncate basal angles, and in the stouter neck supporting the polar 
lobe, as well as in the central scrobiculation. 
107. EUASTRUM SUBHEXALOBUM, West & G. S. West, in Journ. Linn. Soc., Bot. xxxiii. 
1898, t. 16. fig. 7. 
Long. 384; lat. 23:54; lat. isthm. 8 u; crass. 16 u. 
Hab. Paddyfields, Heneratgodha. Paddyfield between Kosgoda and Urahaighasma- 
hendai. 
108. EvastruM FREEMANII, sp.n. (Pl.19.fig. 25.) E mediocre, circiter 1$-plo longius 
quam latum, profunde constrictum, sinu lineari externo ampliato; semicellule 
subsemiellipticee vel oblongo-pyramidatze, 5-lobe, incisuris lateralibus profundis 
similibus et sublate apertis; lobis lateralibus et basalibus similibus subquadratis 
bilobulatis, incisionibus apertis, lobulis truncatis denticulo singulo ad angulum 
unumquemque; lobo polari latissime cuneato et truncato, angulis exterioribus 
dente valido instructis, incisura mediana profunda et subaperta, cirea marginem 
apicalem denticulis circiter 5 utrobique; in centro semicellularum tumore magno 
et in medio lobi basalis uniuseujusque tumore parvo, juxta et supra tumorem 
magnum scrobiculis magnis 4 quadrangulariter dispositis; a vertice vise sub- 
elliptieze, polis truncatis et late emarginatis, tumoribus tribus utrobique; a latere 
visee anguste pyramidate, angulis basalibus prominentibus et rotundatis, lateribus 
late undulatis, apicibus convexis et.tridenticulatis. 
Long. 98 4; lat. 554; lat. lob. polar. (cum spin.) 384; lat. isthm. 13°54; crass. 37 m. 
Hab. Paddyfields, Heneratgodha. Also frequent in paddyfield between Kosgoda and 
Urahaighasmahendai. 
This characteristic species is perhaps nearest to F. rostratum, Ralfs, var. premorsum, 
Nordst., and E. rostratum, var. umbonatum, West & G. S. West, but differs widely in its 
lobulation and in its basal protuberances. Æ. evolutum, West & G. S. West, may possibly 
be said to be of a similar nature, but is less lobulate and has different surface-markings. 
E. Freemanii is also of larger dimensions than the above-mentioned species. 
109. EvASTRUM SPINULOSUM, Delp. in Mem. Accad. Sci. Torino, ser. 2, xxx. 1878, 
p. 97, t. 6. figs. 17, 18. 
Subsp. ArRICANUM, Nordst. in Act. Univers. Lund. xvi. 1880, p. 9, t. 1. fig. 16. 
Long. 60,4; lat. 504; lat. isthm. 10,4. (Pl. 19. fig. 21.) 
Hab. In artificial tank, Peradeniya. 
Subsp. rverMIs, Nordst. l. c. fig. 17. — Euastrum inermius, W. B. Turn. in K. Sv. Vet.- 
JA Akad. Handl. xxv. no. 5, 1893, p. 86, t. 10. fig. 51. 
Long. 57-60 4; lat. 50-55 4; lat. isthm. 115-1354. (Pl. 19. figs. 22, 23.) 
Hab. Paddyfields, Heneratgodha. In artificial tank, Peradeniya. 
Var. CEYLANICUM, var. n. (Pl. 19. fig. 20.) Var. incisuris lateralibus superioribus 
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