a Go'oup of Lycaenid Butterflies. 
487 
nearest. I select ossa, because it is Swinhoe’s name, and 
he more confidently than any one else persists in saying 
there are two species (and only two) in this group, 
though his description of ossa is not more distinctive than 
are those attributed to other names. I have specimens of 
chandala^ apparently so labelled by Moore, that have very 
much the look of ossa, but are really maha. Possibly 
Moore meant the name chandala^ to apply to ossa, and was 
deceived by these specimens of maha into thinking them 
identical. 
A critical examination {i. e. of the genitalia) of the 
type specimens to which all these names apply is the only 
way of settling whether ossa is or is not a synonym of one of 
them. Certainly such names as diluta Siud squalida appear 
to point to one of the most common distinctions that 
enable ossa to be (with some probability) recognised as 
differing from maha. 
The genitalia afford an unmistakable distinction between 
these two forms, and each is quite constant in the con¬ 
siderable number of specimens I have examined. But 
the superficial characters are much less to be depended on. 
Some seasonal forms of maha are I fancy all but in¬ 
distinguishable from ossa, on the upper surface. The 
difference where it exists is that maha always has at least 
some blue of the same character as we (in England) 
regard as belonging to “ Blues ” (such as icarus, thetis, 
aegon, etc.). This may be slight and evanescent, the 
specimen may look quite like ossa, until held at some 
angle that enables the trace of blue to come into view. 
Ossa is without this, and is of a bony whiteness tinted with 
a grey or green tone, that does notvary with the incidence 
of light, or at least never yields a definite blue. 
Maha averages larger than ossa, and in size as in other 
characters appears to be more variable; maha (in my 
series) varies from 20 mm. to 82 mm., ossa from 22 to 
28 mm. 
The seasonal and geographical variation of maha is 
very great, that of ossa apparently much less. 
On the underside the markings are of the same pattern 
in both species, and vary in much the same way. All 
the spots may be markedly black on a pale, even, almost 
white ground, or may be pale, almost identical in tint 
with a pale sienna brown ground-colour, to be made out 
by the slightly paler rings surrounding them. 
