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to lap up the uectar from flowers, mucli in tbe same way as a kitten lana up 

 milk. This is the highest development of the ligida, or tongue, which is known 

 in the insect world. 



In many flies the tongue is without muscles ; it is very pointed, and is 

 used as a lancet. You will call to mind, as a different modification of this 

 organ, the tongue of the cricket. The tongue of the blow-fly, so called, is not 

 simply a tongue, but a modification of the whole of the mouth organs j that 

 of the cricket, on the other hand, is really a tongue. 



On either side of the ligida there are two small organs — ^jaws, which in the 

 beetle serve no object at all ; they are simply jaws on their last legs. All the 

 jaws of insects are legs. Take them in an embryonic condition, and you will 

 find that the jaw and the leg pouches are identical in form, and it is only when 

 developed that the difference is apparent. These little jaws are the paraglossce . 



In the grasshopper, cricket, and dragon-fly, the two pairs of maxillae lie one 

 below the other. They attain their greatest development in the di-agon-fly, 

 and even hide the mouth of the insect, and in the larva of the dragon-fly they 

 are of such dimensions as to cover the ugly head, and enable it to approach near 

 its prey. 



Attached to the two pairs of maxiUoe of crickets, and to the paraglossce of 

 beetles, we find small jointed organs called palpi. These contain a very 

 curious structure, of an extremely delicate nature, in which the ne.rve is 

 probably brought almost in contact with the insects' food. Those attached to 

 the paraglossce ^re called labial palpi, and those which are joined on to the 

 maxillce are called maxillary palpi. 



We now come to the modification of these organs. 



In the bee the parts are all the same as in the beetle, except that the para- 

 glossce, tongue, and 2^'^h^'^ a^© ^^^J i^auch modified. The tongue is much 

 lengthened, like an elephant's tongue in miniature, owing to its highly com- 

 plicated muscular structure. On either side are the labial palj)i, which contain 

 no more joints than in the beetles, but these are enormously drawn out. 

 Whether these are tasting organs, we cannot say, but it is highly probable that 

 this is their use. Between them the tongue works up and down into the 

 nectary of the flower with a very, a marvellously rapid motion, and being 

 covered with fine hairs, it thus brings up the nectar. To aid in this, the tongue 

 terminates in a leaf-like appendage. Not only are the labial palpi developed 

 into a sheath for the tongue, but the maxillce form a covering to the back of 

 the tongue. The maxillary palpi are developed into a knife-like organ, which 

 is used to plaster the wax, or cut leaves, according to the habits of the par- 

 ticular bee. They are very sensitive, exceedingly complicated, and are the 

 building organs of the insect, modified to the use of the different species. For 

 instance, in the upholsterer bee they are curved and scythe-like, and in the 

 rose -cutter bee, they form saws, the teeth of which are set at an angle of 45° 

 to each other. 



In the mouth of the blow-fly we notice the great development of the lower 

 lip or mentum. The tongue is very small, but the mentum is much developed. 

 The lobes are the ^ara^Zossce in a highly developed condition. If the mention 

 is opened out as in Mr. Topping's well known slide, we find the same parts as 

 in the beetle, but in a much more developed state. On the upper side is a groove 

 which forms the floor of the mouth. In this mouth the organs are,' fortunately 

 for us (considering how common an insect the blow fly is), only very rudi- 

 mentary. There are plenty of flies like the blow-fly, which unlike him, can 

 open their mouths and can push in a bundle of six lancets to the skin ; they 



