46 THE ANATOMY OF THE HONEY BEE. 



to our aid and shows clearly that the part in question is the outer 

 lobe or <jalca, for the inner one becomes suialler and smaller in the 

 higher members of the order and iinally disappears. 



The base of the submentum is connected in the l)ee with the upper 

 ends of the cartlines by a flexible, widely V-shaped band, the loi-iim 

 (L/'). The posterior angle of the sulimentum rests in the apex of the 

 lorum. while the tips of the loral arms are movably articulated with 

 the distal ends of the cardines. The name " lora " was given to this 

 structure by Kirby and Spence, but "lorum"' is more correct, since 

 this is the Latin form of the word (meaning a thong or lash). Some 

 recent entomologists have spoken of the structure as consisting of 

 two rods, .thus making the word do duty as a plural, but the thing 

 itself is all one piece. Cheshire and some others have incorrectly 

 applied the name to the submentum. 



The lorum is peculiar to theTIymenoptera, and the reason for it 

 is clear when we examine the attachments of the parts of the proboscis 

 to the head. As already stated, the maxilkr and labium are sus- 

 pended in a large cavity on the back of the head wdiich may be called 

 the /V;.s'.s7/ of the prohoscis (fig. 1) B, PrhFs). The maxilhp are articu- 

 lated by their cardines {Od) to the maxillary suspensoria (fig. 11 

 A, e) at the upper edges of the side walls of the fossa. The labium, 

 on the other hand, is not attached to the solid walls of the cranium 

 but is suspended in the membranous floor of the fossa. This is to 

 afford it freedom of movement during feeding, but, in order to 

 give it more substantial support and to make the regulation of its 

 motions possible, the submentum is slung to the ends of the cardines 

 by the lorum. 



The terminal lobes of the labium and maxillte when not in use 

 are ordinarily folded down beneath the head against the mentum 

 and stipites (fig. ID). When, however, the bee wishes to imbibe a 

 thick liquid such as honey or sirup in large quantity, these parts are 

 straightened out and held close together so as to form a tube between 

 them leading into the mouth, the terminal joints of the labial palpi 

 alone diverging from the rest (fig. 11 A). 



The action of the mouth parts while feeding may be observed quite 

 easily if some bees are given a small amount of honey and then 

 watched through a lens while they are eating. A most convenient 

 method is to put a few^ workers in a small screen-covered cage, such 

 as are used for queen nurseries, spread a small drop of honey on the 

 wire, and then place the cage under a simple microscope. It will be 

 seen that the maxilke are held almost stationary but that the base 

 of the labium slides back and forth between the n_iaxillary bases 

 w4th a very regular to-and-fro movement as if the honey were being 

 either pumped or sucked up into the mouth. It is i)robable that there 

 is a sucking force exerted by the pharynx (fig. 11 B, Phf/) but not 



