15040 — 
the fore wing of the non-mimetic male, viz. the notch just below 
the centre of the inner border of the subapical bar. In this respect 
the brown female is a better mimic than the white, because the 
corresponding notch is in a similar position in Planema tellus 
platyxantha, whereas in the two white-marked female Planemas 
it is above rather than below the centre of the bar. 
In the chrysippus-like forms of the female A. jodutta we have 
merely a combination of the characteristic pattern of the Zellus-like 
female with the subapical bar and adjacent white stria of the 
carmentis female. Natural selection has here been clearly restricted 
to the combination of existing characters. Among all possible com- 
binations, the one that reproduces the pattern of Danaida chrysip- 
pus has alone established itself. 
Acrea althofi DEWITZ. 
Fifteen males and 11 females of this species were captured be- 
tween May 23rd and August 31st, 1909. They afford strong evidence 
of the Müllerian character of the association between the Acræas 
and the Planemas in two out of the three Combinations. Two of the 
females are white-marked and mimic the carmentis female of 
A. jodutta, itself a mimic of two female Planemas, while one with 
yellow markings mimics the non-mimetic male of A. jolutta. 
These 3 examples are included in Table II. The 8 remaining females, 
included in Table III, mimic the fulvous females of A. jodutta, 
themselves mimics of Planema tellus platyxantha. While the fem- 
ales of altho/f prove that the jodutta mimics of Planemas are them- 
selves able to act as models, the peculiarly brilliant upper surface 
colouring of the male a/fhojfi is evidence of the unpalatability that 
is characteristic of the whole sub-family of Acreinc, so far as it 
has been experimentally tested. 
It is of importance to produce detailed evidence in support of the 
conclusion that the female forms of altho/f are in reality mimics of 
mimics rather than mimics of primary models. 
The upper surface pattern of the white-marked females has been 
derived from that of the male by the transformation of the red fore 
wing markings into white, and by a similar modification, accom- 
panied by a broadening and a loss of sharply defined margins, in 
the yellow bar of the hind wing. The changes described above are 
