THE SWALLOW-TAIL BUTTERFLY 
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others, and a large one on each clasper. The legs are pale 
and marked with black. The head is green, with two black 
streaks on each lobe and a central black spot above the mouth, 
and black eye spots. The entire surface, including the head, 
is densely sprinkled with very minute short bristles, each being 
of the same colour as the surrounding ground. 
On the dorsal surface of the first segment is a pair of retractile 
tubercles united at the base in the form of the letter V, of an 
orange or apricot colour, which produce a strong acrid scent, 
resembling pineapple; this organ is protruded only when the 
The Swallow-tail (male). 
larva is irritated. The larval stage occupies 30 days. The 
larva is solitary. 
Pupa. The pupa measures from 28*60 mm. to 31*80 mm. in 
length. The head has two frontal diverging projections; 
the thorax rises to a dorsal conical point and is sunken at the 
waist ; the abdomen tapers to the anal segment, which is 
provided with cremastral hooks. The ventral surface forms 
almost a straight line. In colouring it varies considerably, 
and there are two distinct forms, both apparently equally 
common. One has the whole of the dorsal surface and abdo¬ 
men intense lemon-yellow, with the head and wings greener, 
and a green spiracular stripe. Others have the ground colour 
