DESMIDS FROM SINGAPORE. 165 
The numerous examples of this species seen by us were all 
broader than the forms described from Sumatra by Schmidle. 
The membrane is scrobiculate, the scrobiculations being larger 
over the central thickened area of each semicell, and there are 
fine punctulations between these scrobiculations; in age the 
membrane becomes yellow. The granules are conical and vary 
somewhat in length ; the breadth of the isthmus varies consider- 
ably, and the apices of the semicells are in all cases slightly 
truncate. 
As we have previously pointed out (Trans. Linn. Soc. Ser. II. 
(Bot.) v. (1895) p. 229, footnote), C. dentatum, Wolle (cfr. West 
& G. S. West, l. c. p. 249, t. 15. ff. 10, 11), is by far the nearest 
ally of this species. Schmidle represents the conical granules too 
large relatively to the magnification of the cells; the figures 
given by Borge in Bihang Vet.-Akad. Handl. xxii. no. 9, t. 3. 
ff. 35, 36, are more correct in this respect, but the granules are 
more acute than any we have seen. 
C. Stuhlmannii, Hieron. (in Engler, Die Pflanzenwelt Ost.- 
Afrik. u. d. Nachbargebiete, Theil C, 1895, p. 19), is most 
probably a form of this species. 
38. COSMARIUM MARGARITATUM, Roy et Biss. in Journ. Bot. 
xuv. (1886) p. 194. 
Long. 65 u; lat. 57 u; lat. isthm. 25 p. 
39. C. SUBDECORATUM, n. sp. (Pl 8. fig. 13.) 
C. mediocre, 1jplo longius quam latius, profunde constrictum, 
Un an gusto-lineari extremo ampliato ; semicellule truncato- 
Pyramidate, angulis inferioribus et superioribus rotundatis, 
'ateribus convexis, apicibus subrectis; membrana granulis quin- 
cuncialiter ordinatis, seriebus horizontalibus circiter 7, seriebus 
ciuis circiter 10, serobiculis triangularibus 6 cirea granulum 
TL quemque ; a vertice vise oblong:e, polis rotundatis. 
AM HS lat. 53 H; lat. isthm. 17:5 p; crass. 29 p. 
Linn. § S. from C. decoratum, West & G. S. West in Trans. 
size ite di er. T. (Bot.) v. (1895) p. 61, t. 7. f. 21, 1n its smaller 
vertical ceper constriction, its much fewer granules, and in its 
triangula wi moreover, the sides and not the angles of the 
ifer hi Scrobiculations are directed towards the granules. It 
* irom C, multiordinatum, West & G. S. West in Journ. 
