176 MESSRS. W. WEST AND G. S. WEST ON 
the general outline of which is represented by Stawrastrum unicorne. That they can only 
be regarded as varieties of one species is evident from their close resemblance and from 
the fact of the occurrence of yet another variety (from Ceylon) slightly different 
from any of the above, but connecting typical S. wnicorne with its varieties nodiferum 
and eximium. 
Var. CEYLANICUM, var. n. (Pl.21.figs. 16,17.) Var. apicibus capitatis processuum cum 
annulo denticulorum 4 et spina terminali elongata introrsum curvata instructis ; 
denticulo parvo ad marginem sinus ut in var. nodifero. 
Long. sine proc. 22-23; long. cum proc. 25-26; lat. cum proc. sed sine spin. 
27-31 x; lat. cum spin. 46-50; lat. isthm. 8 u. 
Hab. Paddyfields, Heneratgodha. 
The apices of the processes of this variety differ from those of var. nodiferwm and 
var. eximium in the possession of the long and slightly incurved spines present in typical 
S. wnicorne. 
220. STAURASTRUM BIFIDUM, Bréb. in Ralfs, Brit. Desm. 1848, p. 215; Lund. in Nov. 
Act. Soc. Scient. Upsala, ser. 3, viii. 1871, p. 62, t. 4. fig. 2. 
All the forms seen had a more or less straight apex, and the two spines at each angle 
were not in a horizontal plane. Long. 31; lat. sine spin. 33-35 w; lat. isthm. 11 y. 
Hab, Paddyfields, Heneratgodha. 
221. STAURASTRUM BRASILIENSE, Nordst. in Vidensk. Medd. f. d. naturh. Foren. Kjoben- 
havn, 1869, p. 227, t. 4. fig. 39. 
Var. TRICORNUTUM, nob. A tricornutum, Wolle, 1880; Desm. US. p. 145, t. 47. 
figs. 1, 2. 
Forma paullo minor. Long. sine spin. 80; lat. sine spin. 71, cum spin. 111p; 
lat. isthm. 25 y. 
Hab. Paddyfield between Kosgoda and Urahaighasmahendai. 
There is no doubt whatever that S. tricornutum, Wolle, is a variety of S. brasiliense, 
Nordst. as it only differs in the convex apex of the semicells and in the triangular 
vertical view. It is also considerably larger than typical S. brasiliense, but no 
larger than S. brasiliense var. Lundellii, West & G. S. West. 
222. STAURASTRUM ENSIFERUM, W. B. Turn. in K. Sv. Vet.-Akad. Handl. xxv. 1893, 
no. 5, p. 109, t. 14. fig. 22. 
Long. sine spin. 34—37 », cum spin. 49-54, ; lat. sine spin. 29-32:5 u, cum spin. 42- 
46 u; lat. isthm. 15:5 a. 
Hab. Paddyfields, Heneratgodha. 
Some specimens possess only two spines at each angle, others possess three, and it is 
