160 MESSRS. W. WEST AND G. S. WEST ON 
have only five pairs on each side, and they have in addition a few scattered smaller spines 
within the basal angles. 
141. XANTHIDIUM QUADRIDENTATUM, sp. n. (Pl. 20. fig. 21.) X. submediocre, circiter 
1i-plo longius quam latum (sine spinis), profunde constrictum, sinu lineari extremo 
valde ampliato; semicellule pyramidato-semicirculares, angulis inferioribus sub- 
rotundatis dente parvo instructis, lateribus cum serie spinarum 4 (spinis gradatim 
majoribus apicem versus), apicibus latis truncato-convexis spina majore valida ad 
angulum superiorem unumquemque, serie granulorum depressorum magnorum 
6 intra et juxta marginem apicis, in centro membrana incrassata luteo-brunnea 
cum scrobiculis 8-9; a latere vise subcirculares, seriebus divergentibus 2 spinarum 
et granulorum apicem versus, in medio apicis cum spina valida, lateribus incrassatis ; 
a vertice vise late ellipticze, serie spinarum et granulorum intra marginem lateralem 
unumquemque, polis rotundatis spinulatis, in medio utrinque incrassatis. 
Long. sine spin. 46 u, cum spin. 514; lat. (s. spin.) 38 u; lat. isthm. 10 u; crass. 26 u. 
Hab. Paddyfields, Heneratgodha. 
This species somewhat resembles X. lepidum (p. 159) and X. ceylanicum (p. 158), but 
can be readily distinguished from either. It differs from X. lepidum in its general form 
and proportion in all views, in the arrangement, number, and form of its spines, in the 
large single spines at the superior angles, and in the six flattened granules within the apex. 
X. lepidum possesses only four flattened granules within the apex, and it agrees with 
X. quadridentatum in having these granules arranged in a continuous series with the 
lateral paired spines. These series are subparallel in X. lepidum, but widely divergent 
in X. quadridentatum. 
From X. ceylanicum it is chiefly distinguished by its larger size and different outward 
form, by the presence of the six flattened granules within the apex, and by the large single 
spines at the superior angles. It is also without the large granule present above the 
isthmus in X. eeylanicum, and the central scrobiculated area is relatively much smaller. 
Compare also with X. torquatum, W. B. Turn. (in K. Sv. Vet.-Akad. Handl. xxv. no. 5, 
1898, p. 102, t. 22. fig. 8). 
142. XANTHIDIUM VARIABILE, West & G. S. West, in Journ. Bot. xxxviii. 1900, p. 291. 
X. Smithii, Arch., var. variabile, Nordst. 1887; in K. Sv. Vet.-Akad. Handl. 
xxii. no. 8, 1888, p. 44, t. 4. figs. 27-29; West & G. S. West, in Journ. Roy. 
Mier. Soc. 1896, p. 156, t. 4. fig. 10; G. S. West, in Journ. Linn. Soc., Bot. xxvii. 
1899, p. 386, t. 8. figs. 20-22. 
Long. (sine spin.) 224; lat. sine spin. 21 u, cum spin. 23:5 u; lat. isthm. 6; crass. 15 s. 
Hab. Paddyfield between Kosgoda and Urahaighasmahendai. 
143. XANTHIDIUM INCONSPICUUM, sp. n. (Pl. 20. fig. 26.) .X. minutissimum, paullo 
longius quam latum (sine spinis), profunde constrictum, sinu lineari extrorsum 
leviter aperto; semicellul:e angulari-oblongs, angulis inferioribus rectangularibus 
et leviter rotundatis, angulis superioribus truncato-rotundatis, apicibus late truncatis 
Peer 
