152 MESSRS. W. WEST AND G. S. WEST ON 
1899, xxiv. Afd. 3, no. 12, p. 26, t. 2. fig. 31), but is distinguished by the much deeper 
and narrower lateral incisions, the different form of the polar lobe, and the different 
markings on the cell-wall. The protuberances are not granulate, but the middle one of 
the basal series of three is tripartite, and above the basal protuberances are a number 
of scrobiculations. Moreover, the apical incision is quite closed (not widely open as in 
-Euastrum coralloides), and there are a number of granules within the margins which are 
quite absent from Æ. coralloides and its var. trigibberum. 
From Æ. geometricum, sp. n., it is distinguished by its greater breadth, the different 
form of the sinus, the emarginate lateral lobules, and the elevated apical part of the polar 
lobe. The median basal tumour and the granules within the margin are also different. 
115. EvASTRUM TRUNCATUM, Josh. ‘Burm. Desm.,' in Journ. Linn. Soc., Bot. xxi. 1886, 
p. 639, t. 23. figs. 6, 7. 
'The following is an amended description of this species :— 
E. submediocre, circiter 11—12-plo longius quam latum, profundissime constrictum, sinu 
angusto-lineari extremo subampliato; semicellule trilobs, incisuris lateralibus 
profundis angusto-linearis; lobis lateralibus subtrapeziformibus, angulis subro- 
tundatis vel seepe truncato-emarginatis, lateribus plerumque subretusis (nonnunquam 
subundulatis); lobo polari rectangulari-trapeziformi, lateribus leviter retusis vel 
subrectis, apice late retuso; tumore magno in lobo laterali unoquoque, tumore 
magno in centro et tumore parvo intra marginem lateralem unumquemque lobi 
polaris, scrobiculo maximo in centro semicellularum ; a vertice vise suboblonge, 
polis rotundatis, tumoribus magnis binis subdistantibus utrobique; lobo polari a 
vertice viso oblongo-elliptico, polis subtruncatis, tumoribus tribus utrobique; a latere 
visee ovatee, tumore magno prope basin et tumore minore apicem versus utrobique, 
apice angulari-rotundato. 
Long. 46-50(—65 Josh.) u; lat. 29-83(—87 Josh.) u; lat. lob. polar. 23-26 u; lat. isthm. 
8:5-9(-16! Josh.) u; crass. 224. (Pl. 20. figs. 9, 10.) 
Hab. Paddyfields, Heneratgodha. Paddyfield between Kosgoda and Urahaighas- 
mahendai. 
We feel convinced that the plant we have described above as E truncatum, Joshua, is 
precisely the same as the plant Joshua examined from Burmah. The resemblance 
between our specimens and his figure of E truncatum is greater than the resemblance 
between the actual specimens and Joshua's figures of many of his species. Evidence 
that our plant is the same as Æ. truncatum is also sustained by the fact that many other 
of Joshua's species were found along with it, and all of them differed considerably in 
detail from the inaccurate illustrations given by that observer. Joshua, in his description 
(L. c. p. 639), mentions the two large protuberances near the base of the semicells, one 
being situated in each lateral lobe, but fails to mention the protuberances of the polar 
lobe and the large scrobiculation in the centre of the semicells. 
E trifolium, Cohn (* Desm. Bong.,' Festschrift natur. Ges. zu Halle, 1879, p 11, t. 11. 
fig. 13), is undoubtedly the nearest species to E. truncatum, possessing three well-marked 
lobes to each semicell, each lobe having a large protuberance in the centre; the form of 
