104 HALF HOURS WITH I^-SECTS. [rACKARD. 



project out from near the end of the body. From these two 

 tubes issues the so-called honey dew, the delight of the sweet 

 toothed ant. When a brood of aphides are busily engaged 

 in tapping the stems of some plant, and the honey dew is 

 dropphig upon the ground or leaves below, a procession of 

 sable ants enliven the scene. 



This sweet fluid is also designed to afford nourislunent for 

 the young as soon as hatched. Both Bonnet and the Belgian 

 naturalist Morren observed that the young Aphides as soon as 

 born sucked up the fluid with their beaks, and thrived upon 

 that for a.while, before attacking the juices of the plant itself. 

 It has been a matter of curiosity to us how this thin fluid 

 is secreted. Moi-ren* has demonstrated that these tubes are 

 in reality modified respirator}' organs, as Bonnet had sup- 

 posed. They are simply tubular elongations of the skin 

 with a hole at the end, into which the air enters, while the 

 sweet fluid escapes from the same hole. On dissecting the 

 little creature, a task requiring much time and patience, 

 Morren found a net-work of air tubes (tracheae) near the base 

 of each tube. This tube, he says, is "onl}^ a prolonged 

 stigma, and it becomes evident that it is the air of these tra- 

 cheae which forces out the fluid with which this appendage 

 is often filled." At the base of the tube he also found a 

 gland which secretes the sweet liquid. The latter passes 

 into the tube or excretory canal at the same time as the air 

 within pi'csses out. The viscous liquid is thus thrown out 

 during expiration. Morren tells us that he has "several 

 times seen the 3'oung Aphides suck the end of these tubes 

 while holding their beaks near it. This always happened 

 whenever I was able to have the females bring forth their 

 young in vials Mithout any leaves to serve as food for either 

 the young or its mother. Now a gland situated on the sur- 

 face of the bod}', provided with an excretory canal, and se- 

 creting a sweet fluid intended to nourish the young is in fact 

 *A:iiiales des S<nences Nuturelles. Tome P. Second series, ISM. Paris. 



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