The Life-History and Anatomy of Butterflies 
word pwtfaXov ( rhopalon ), which means a club , and the word xepag 
(keras) which means a /;orw. 
It will be observed from what has been said that the head in 
these creatures is to a large extent the seat of the organs of sense 
and alimentation. What the function of the antennae may be is 
somewhat doubtful, the opinion of scientific men being divided. 
The latest researches would indicate that these organs, which 
have been regarded as the organs of smell and sometimes 
as the organs of hearing, have probably a compound function, 
possibly enabling the creature to hear, certainly to smell, but also, 
perhaps, being the seat of impressions which are not strictly like 
any which we receive through our senses. 
Thorax .—The thorax is more or less oval in form, being 
somewhat flattened upon its upper surface. It is composed of 
three parts, or segments, closely united, which can only be dis¬ 
tinguished from one another by a careful dissection. The anterior 
segment is known as the prothorax, the 
middle segment as the mesothorax, and the 
after segment as the metathorax. The legs 
are attached in pairs to these three subdivi¬ 
sions of the thorax, the anterior pair being 
therefore sometimes spoken of as the pro- 
thoracic legs, the second pair as the meso- 
thoracic legs, and the latter pair as the 
metathoracic legs (Fig. 34). 
side of the mesothorax are attached the 
anterior pair of wings, over which, at 
their insertion into the body, are the tegulce, or lappets; on either 
side of the metathorax are the posterior pair of wings. It will 
be seen from what has been said that the thorax 
bears the organs of locomotion. The under side 
of the thorax is frequently spoken of by writers, 
in describing butterflies, as the pectus , or breast. 
The Abdomen. —The abdomen is formed nor¬ 
mally of nine segments, and in most butterflies 
is shorter than the hind wings. On the last seg= 
ment there are various appendages, which are 
mainly sexual in their nature. 
Fig. 34. — Colias philo- 
dice: a , antenna; p , extrem- 
On pjtlw j - ty of P al P us ; Ph prothoracic 
wu eiuici ] e g. mesothoracic leg; 
hi, metathoracic or hind 
leg; /, proboscis. 
Fig. 35. —Leg ot 
butterfly: c, coxa; 
tr, trochanter; f, 
femur; t, tibia; 
tar, tarsi. 
The Legs. — Butterflies have six legs, arranged in three pairs, 
as we have already seen. Each leg consists of five parts, the 
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