22 



THE ANATOMY OF THE HONEY BEE. 



basal joint called the coxa (Cr). Beyond this is a smaller joint 

 called the troclxititcr {Tr)^ this is followed by a long and strong 

 segment, the fciinir (F) , which extends ontward from the body, while 

 bending (h)wnward from its distal end is the long and slender flhid 

 (Th), followed finally by the foot, or farsiis (Tar). The tarsus itself 

 consists typically of five small segments of wliich the last bears a pair 

 of cJaws (CJa). The under surfaces of the tarsal joints are often 

 l^rovided with small cushions or pads called pid riU't. Those between 

 the claws are generally specially })roniine'nt and are called the 

 em podia {Kiiij)). The leg varies greatly in shape in diflerent in- 

 sects but usually preserves all of these parts. The segments of the 

 tarsus, however, are frequently reduced in munber. 



The adult wing^ is a thin expanse of in( mhrane supi^orted by hollow 

 branching rods called veins. It originates as a hollow outgrowth of 

 the body-wall, l)ut soon becomes flattened out dorso-ventrally and the 



,A ^ cu, 



Cu,^<« 



Pig. 6. — Diagram of generalized insect wing and its artieulatiou to first plate (V) of 



the tergum. 



contained tracheae or air tubes mark out the courses of the veins. 

 These veins form various patterns in different insects, but they can all 

 be derived by modification from one fundamental plan. This plan is 

 shown diagrammatically by figure G. The first vein, which usually 

 forms the anterior margin of the adult wing, is the costa {C). The 

 next vein is the suhcosta (Sc), which in typical cases divides into 

 two branches (Sc-^ and Sco). The third and usually the principal 

 vein is the radius {R). It divides dichotomously into five branches 

 {R^ to Rr,)^ the anterior branch of the first fork remaining single. 

 The next vein is the media (J/), which forms four branches (J/^ to 

 J/J. The fifth is the cahitus (Cu), which again is two-branched. 

 The remaining veins are called the amds and are designated indi- 

 vidually as the fi/'f<f anal (iA), second anal {'2A), etc. 



Several cross- rci /is of common incurrence shoulcl be noted. The 

 first is situated near the base of the wing between the costal and 

 subcostal veins and is known as the humeral cross- vein. A second 



