60 THE FERTILISATION OF FLOWERS. [PART II. 
at their edges, form a tube out of which only the part uw of the 
tongue protrudes. But almost simultaneously with these move- 
ments, the bee draws back the basal part of its tongue into the 
hollow end of the mentum, and so draws the tip of the tongue, 
moist with honey, into the tube, where the honey is sucked 
in by an enlargement of the foregut, known as the sucking 
stomach, whose action is signified externally by a swelling of the 
abdomen.” 
Fig. 19 represents the head of a humble-bee in the suctorial 
position. If now the base of the tongue is drawn back into the 
hollow of the mentum (as shown in Fig. 20), the tip (wv) is 
drawn, wet with honey, into the tube. If the cardines (c, Fig. 19), 
F 
Ga. 19.—Head of Bombus hortorum, 2, with proboscis halt extended. 
~ 
Seen from the side (x 7).. Lettering as in Figs. 11 and 18, 
which are now directed vertically downwards, are rotated back- 
wards, the base of the suctorial tube (at pm in Fig. 19) will 
be drawn back to the opening of the mouth (between the base 
of the mandibles and upper lip), and by a sucking action of the 
sides of the body [and (?) a simultaneous action of the erectile 
hairs on the tongue*], the honey is quickly carried into the 
mouth. 
1 In Apide and Vespide the “sucking stomach” is simply a lateral fold of the 
foregut ; in Crabronide it is a vesicle attached by a short, narrow duct, much as 
in Diptera. ' 
2 Of. the remarks on Lamium albwm. 
3 I came to the above conclusion with regard to the action of the whorled hairs 
from experiments made on bees and humble-bees under chloroform. In these, some- 
times, if the tip of the tongue was dipped in syrup before complete loss of conscious- 
ness, the suctorial movements took place so slowly that their separate stages could be 
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