146 MESSRS. W. WEST AND. G. S. WEST ON 
* species " are of about the same size and both have the same outward form. Pleuro- 
tenium maximum has one moderately large inflation at the base of the semicells, and 
P. Archerti may have one or two. But we have already shown (Journ. Bot. 1897, 
p. 80) that P. maximum may also possess one or two (or even three) basal inflatious, 
so that this character is useless. Moreover, the relative size of the basal inflation 
of P. maximum is very variable, and certainly includes every condition exhibited by 
Delponte's P. Archerii. 
Var. PHZODERMUM, nob. Pleurotenium pheodermum, Schaarschm. in Magyar Tudom. 
Akad. math. és Természettud. Kózlemények, xviii. 1883, p. 278, t. 1. fig. 22. 
P. Archerti, Delponte, var. triannulatum, Schaarschm. J. e. fig. 23. P. Archerit, 
Gute. in Kom. fizyogr. Akad. Umiej. Krakow, xxx. 1894, t. 3. fig. 14. Var. 
semicellulis paullo inflatis, distinete attenuatis apicem versus, supra inflationem 
basalem majorem undulis parvis 2-4; membrana scrobiculato-punctata, achroa, 
lutea vel brunnea. 
Long. 626-646 u; lat. ad bas. semicell. 37-484; lat. ad med. semicell. 32:5-38'5 u ; 
lat. apic. semicell. 21-22 x. 
Hab. Paddyfield between Kosgoda and Urahaighasmahendai. In artificial tank, 
Peradeniya. 
The two plants described and figured by Schaarschmidt as P. pheodermum and 
P. Archerii, var. triannulatum, are undoubtedly representatives of the same species, and 
we think both fall under P. maximum as a variety, which we propose to name var. 
pheodermum. The number of small undulations above the large basal one varies from 
about two to four. The cell-wall is scrobiculate-punctate as in typical P. maximum. 
The name “ pheodermwn " was applied by Schaarschmidt to a form with a brown cell- 
wall, and although specimens are more frequently met with which possess a colourless 
cell-wall, Schaarschmidt’s name must be retained. 
Genus 'TRrPLOCERAS, Bail. 
98. TRIPLOCERAS GRACILE, Dail. 1851; Nordst. in K. Sv. Vet.-Akad. Handl. xxii. 
no. 8, p. 64, t. 7. fig. 12. Docidium gracile, Wittr. in Nov. Act. Soc. Sci. Upsala, 
ser. 3, vol. vii. 1869, pt. 21, t. 1. fig. 10. 
Long. 211-332 4; lat. 25-28 p. 
Hab. Paddyfields, Heneratgodha. 
Genus TEgTMEMORUS, Ralfs. 
99. TETMEMORUS GRANULATUS, Ralfs, 1844; Brit. Desm. 1848, p. 147, t. 24. fig. 2, t. 33. 
fig. 1. Closterium granulatum, Bréb, 1839. 
Hab. Paddyfields, Heneratgodha. Pool in glen by roadside, near Bandarawella 
altit. 4000-5000 ft.). 
