94 THE AUSTRALIAN NATURALIST. 
second segment, behind. the head; with a red osmaterium ; 
this is a Y-shaped retractile tentacle which, when the larva is 
disturbed is protruded, at the same time emitting a strong 
odour. This odour often reveals the presence of a larva when 
searching citrus trees. The pupa, as is usual in this family, 
is attached by the tail and by a silken girdle round the middle; 
it is either green or mottled brown in colour, assimilating 
much to the particular colour of the stem of the plant to which 
itis attached. The duration of the pups stage is uncertain, 
and depends to a great extent on external causes. Mr. R. H. 
Turner one year at Mackay found that one batch of pupse 
reared from larve emerged some considerable time before a 
previous batch which had also pupated in his possession. 
In Sydney the perfect insect is usually on the wing early in 
the year, and is the largest butterfly in this neighbourhood. 
_ The sexes are very dissimilar, the male being black above with 
a white bar of spots across the apex of the forewing, a red 
anal spot on the hindwing, which also has a large central 
white area, which is not represented, on the underside. The 
female is much paler in colour, haying no white bar on the 
forewing, while the white area of the hindwing is found both 
above and below as well as a nearly complete row of red spots. 
2. History in literature.—As 18 only natural, the fact of the 
dissimilarity of the sexes has caused some little confusion. 
When the species was first sent to Hngland by Mr. Alexander 
Macleay from. Port Jackson, the sexes were considered as 
distinct species, and as such were described by Donovan in 
1805 in the “Insects of New Holland.” On plate 14, he pro- 
posed the name Papilio xgeus for the female, and on plate 15 
the name P. erectheus. Neither Hiibner (1816), Godart (1809), 
nor Boisduvyal (1832) recognised the sexes as one species, but 
Lucas (1835) and Boisduyal (1836) speak of both sexes under 
the name of P. erectheus. Felder in 1864 revised the Papilio 
very carefully and speaks of our Papilio as P. exgeus, treating 
P. erectheus as a synonym. Kirby (1871), in his masterly 
catalogue, does the same, and more recently Rothschild (1895) 
concurred in this. Masters and Miskin, who in their catalogues 
in the main followed Kirby’s Catalogue, depart from it in this 
instance and use the name P. erectheus, but assign no reason, 
nor have I been able to find any reason why the name ageus 
should be used in Hurope and the name erectheus in Australia. 
As the name xgeus appears first in Donovan’s work, is that 
adopted by the three principal monographers who recognised 
the sexes as the same species, it is, I think, as well that we in 
Australia should fall into line and adopt the name sgeus for 
this species, as has already been done by quite a number of 
Entomologists here, 
