The Life Processes of the Individual 
139 
is pulled and pushed through the maxillae. This motion 
doubtless effects a pumping action, bringing the liquid 
through the temporary tube 
formed by the curling of the 
glossa. It is probably sucked 
farther by the pharynx. The 
glossa is also retracted into 
the mentum and this with its 
own contractility gives it great 
flexibility of movement. 
Thorax. 
As explained earlier (p. 99), 
the functional thorax of the 
bee (Figs. 73 and 74) con¬ 
sists of the three segments 
which form the thorax in 
other orders of insects and 
the segment which is the first 
abdominal segment of other 
orders. This modification is 
found in most other Hymen- 
optera 1 but the fact has seem¬ 
ingly escaped most writers on 
bees. The prothorax (1st 
thoracic segment) is reduced 
and the first pair of legs, 
arising from this segment, are 
loosely attached. The meso- 
thorax (2d thoracic segment) 
is specially well developed to 
accommodate the large mus¬ 
cles which propel the fore wings, while the metathorax (3d 
thoracic segment) is reduced, consisting only of a narrow 
plate ( T3 ), the metatergum, and two lateral plates on 
Fig. 73. — Dorsal view of ventral 
walls and internal skeleton of 
worker. Much enlarged. 
■Snodgrass, H. E., 1900. Proc. U. S. Nat. Mus., XXXVI, pp. 511- 
695. 
