366 



INTRODUCTION TO ZOOLOGY 



Tarsus 



flying the two act as one. When at rest tlie front wings slip 

 over the back wings, thus releasing the lock, and both then 



lie horizontally over the back, but 

 when they are again spread for 

 flight, once more the two margins 

 are automatically hooked together. 

 The legs are worth detailed 

 study, for each pair has some 

 Fig. 291. —Wings from the special adaptation fitting it to per- 

 right side of a Honey Bee, form some special function, besides 



seen from below. ^j^^ g^^^^^.^^ function of locomotion 



c, Upturned edge of the front wing; ju yf^-^^\ thev all share alike. 



a, hooks on the back wing. -ri i i i • i i . 



Jiach leg ends in two long and two 

 short movable claws with a 

 little pad between them. The 

 claws enable the bee to climb 

 rough surfaces, and to hang, 

 when necessary, clinging by 

 them (see p. 369) ; while the 

 pad, which can secrete a sticky 

 substance, enables it to climb 

 up smooth slippery surfaces as 

 a fly does (p. 330). The joints 

 of the legs are similar to those 

 found in all insects, but each 

 leg has on it a characteristic 

 special structure ; on the first 

 leg, at the joint between the 

 fourth and fifth segments, 

 there is a special little ar- 

 rangement for cleaning the 

 antennae and proboscis and 

 the hairs that are present be- 

 tween the facets of the com- 

 pound eye. This is known as 

 the " comb," and consists of 

 a small depression lined with 

 hairs on the fifth segment, 

 and a Jittle prong which pro- 

 jects over this from the fourth 

 segment. On each middle 



Fig. 292. — Tlie Legs of a Honey Bee. 

 A, Front leg ; B, middle leg ; C, back leg. 



