ANATOMY or THE BEE. 



503 



glossa. This organ (Fig. 3, D, Ols), ordina- 

 rily called the "tongue," is terminated by 

 a delicate, sensitive, spoon-like lobe known 

 as the labella (Fig. 3, A, B, and D, LU), and 

 has a groove [k) running along its entire 

 length on the ventral side. Within the 

 glossa this groove expands into a double- 

 barreled tube (Fig. 8, E, Lum). A flexible 

 chitinous rod (r) lies along the dorsal wall of 

 this channel, which is itself provided with a 

 still finer groove [l) along its ventral surface. 

 Thus the very smallest quantity of nectar 

 may find a channel suited to its bulk 

 through which it may run up to the base 

 of the glossa by capillary attraction. But 

 since the glossal channels are ventral the 

 nectar must be transferred to the dorsal 

 side of the labium by means of the para- 

 glossse, the two soft lobes (Fig. 3, D and F, 

 Pgl) whose bases are on the upper side of 

 the mentum, but whose distal ends underlap 

 the base of the glossa, and thus afford con- 

 duits for the nectar around the latter to the 

 upper side of the labium. The glossa is 

 highly extensible and retractile by means of 

 muscles attached to the base of its rod, and 

 its movements when a bee is feeding are 

 very conspicuous, and interesting to watch. 



The thorax of any insect carries the wings 

 and the legs. The two wings of the bee on 

 each side are united to each other by a series 

 of minute hooks so that they work together, 

 and the four wings are thus practically con- 

 verted into two. Each wing is hinged at its 

 base to the back, and pivoted from below 

 upon a small knob of the side wall of the 

 thorax. The up-and-down motion of the 

 wings is produced, not by muscles attached 

 to their bases, but by two sets of enormous 

 muscles, one vertical and the other horizon- 

 tal, attached to the walls of the thorax, 

 whose contractions elevate and depress the 

 back plates of the thorax. Since the ful- 

 crum of each wing is outside of its attach- 

 ment to the back, the depression of the 

 latter elevates the wings, and an elevation 

 of the back lowers the wing. But the bee 

 flies by a propeller-like action, or figure-8 

 motion of the wings. This is produced by 

 two other sets of much smaller muscles act- 

 ing directly upon the wang bases, one before 

 and the other behind the fulcrum of each. 

 The combined result of all these muscles is 

 that the down stroke of the wing is accom- 

 panied by a forward movement and a deflex- 

 ion of the anterior edge, while the up stroke 

 reverses this. 



The legs of the bee are too familiar to 

 need any extensive description here. Their 



special characters, such as the antennae- 

 cleaners on the first and the pollen-baskets 

 and brushes on the last, are illustrated in 

 Fig. 4. The tarsi are each provided with a 

 pair of terminal daivs (E, Cla], by means of 

 wiiich the bee clings to rough object?, while 

 between the claws is a sticky pad. the tmpo- 

 dium (Emp), which is brought into play 

 when the bee alights on or walks over any 

 smooth surface like glass. 



The hind part of the thorax of ];ees, was] s, 

 and their allies is composed of a segment 

 which, in other insects, is a part of the abdo- 

 men. It is known as the propodium. The 

 middle division of the body of a bee, wasp, 

 or ant, therefore, is not exactly the equiva- 

 lent of the thorax of a grasshopper, fly, or 

 butterfly. 



The abdomen of the bee has no appendages 

 corresponding with those of the head or 

 thorax; but it bears tw^o important organs, 

 viz., the wax-glands and the sting. The 

 wax-glands are simply specially developed 

 cells of the skin on the ventral surfaces of 

 the last four visible abdominal segments of 

 the worker. There are only six segments vis- 

 ible in the apparent abdomen; but remem- 

 bering that the propodeum of the thorax is 

 really the first, the wax-glands occur, there- 

 fore, on segments four to seven inclusive 

 (Fig. 1, IV-VII). The wax secreted by the 

 glands is discharged through minute pores 

 in the ventral plate of each segment, and 

 accumulates in the form of a little scale in 

 the pocket above the underlapping ventral 

 plate of the segment next in front. 



The sting is such a complicated organ that 

 it is very diflicult to describe it clearly in a 

 few words. Fundamentally it consists of 

 three slender, closely appressed i ieces form- 

 ing the sharp piercing organ that projects 

 from the tip of the abdomen (Fig. 1, Stn), 

 and of two soft finger-like lobes, sometimes 

 also visible, all of which arise from three 

 pairs of plates belonging to the eighth 

 and ninth segments of the abdomen, lait 

 which are concealed within the seventh 

 segment. 



Fig. 5 show^s, somewhat diagrammatically, 

 all the parts of the left side. The acute 

 stinging shaft swells basally into a large 

 bulb [ShB) which is connected by a basal 

 arm on each side with two lateral plates [Ob 

 and Tri). The finger-like lobes, called the 

 'palpi of the sting {StnPlp) are carried also by 

 the low^er of these two plates {Ob] while the 

 upper {Tri) carries the third and largest 

 plate (Qd) which partially overlaps the 

 lower {Ob). 



