128 
BORNEAN CICADIDAE, 
General distribution : Malaya. 
Java, Sumatra, Sulu Islands and Perak. 
This is distinctly a variable species; and there are two 
marked varieties in the Sarawak Museum which are per- 
haps worthy of comment. They are both females and are 
noticeable for the reduced black markings on the pronotum 
and mesonotum. The two black central fasciz of the 
mesonotum become reduced towards the pronotum, so as. 
to leave a small central patch of ground-colour, while in 
the typical form these fasciz grow wider and finally meet 
on the border of the pronotum. The dark pronotal mark- 
ings are also reduced. 
There is another curious aberration in this collection, 
taken on the upper waters of the Limbang River (April 
1910). In this example the neuration of the left tegmen 
is abnormal in two places. The first ulnar area is closed 
by an additional vein about 2 rm. short of the apical 
end of that area. The third apical area is also shortened 
by an additional vein about 2 mm. short of the basal end 
of that area; the addition of these two small veins thus 
results in the formation of two small post-ulnar or pre- 
apical cells. The second abnormality is produced by a 
small additional vein enclosing the apex of the fourth 
ulnar area. The neuration of the left tegmen is normal. 
I have also noticed a small aberration in the neuration 
of a specimen of Dundubia rufivena, Walk.; and it is 
perhaps interesting to note that the neuration of Czcadidae 
is evidently prone to variation while that of Lepidoptera is 
so stable that some systematists have been led to base 
their classifications on that character alone. 
Rihana umbrosa, Dist. 
Ann. Mag. Nat. Hist. (7) xiv. p. 330 (1904). 
Id. Syn. Cat. Hom. p. 34 (1906). 
This species is confined to Borneo. 
Jour. Straits Branch 
