37 ^ the study of insects . 
thorax. These have been termed osmateria (os-ma-te'ria), 
and are supposed to be 
organs of defence; for 
they exhale when pushed 
out an odor which in some 
species is exceedingly dis¬ 
agreeable. 
The chrysalids are 
thickened in the middle 
and taper considerably at 
each end ; they are more 
or less angulated, and have 
certain parts excessively 
produced ; they are sus¬ 
pended by the tail and by 
a loose girth around the 
middle. 
This family includes 
two well-marked subfami¬ 
lies, which are distin¬ 
guished as follows :— 
A. Hind wings with a tail¬ 
like prolongation ; ground- 
color of wings black ; radius 
of fore wings five-branched; the base of vein VIII of fore wings 
preserved as a spur-like branch of vein VII (Fig. 456). p. 376 
Pa PI LI ONI NiE. 
AA. Hind wings without tail-like prolongation ; ground color of 
wings white; radius of fore wings four-branched ; vein VIII of fore 
wings wanting, p. 380. Parnassiinas 
Subfamily Papilionin^: (Pa-pil-i-o-ni'nae). 
The Swallow-tails. 
These magnificent butterflies are easily recognized by 
their large size and the tail-like prolongations of the hind 
wings. The ground color of the wings is black, which is 
