424 



Stings.— AM. the apparatus by which the poisonous matter 

 is secreted, and the ducts by which it is conveyed to the 

 sting, as well as the sting- itself, are best shown in fluid, but 

 as the dissection of these delicate parts requires very con- 

 siderable care, the plan of drying, and then mounting them in 

 balsam, is more commonly practised ; the subjoined list wiU 

 point out the best insects for the purpose : — 



Bee, Ichneumon fly. 



Hornet, Wasp. 



Stomachs. — In some insects, such as the bee, the ramifica- 

 tions and anastomoses of delicate tracheae may be shown upon 

 the thin walls of this viscus; in others, the glandular 

 structure of the organ is well seen, whilst, in a few, the tritu- 

 rating apparatus, or gizzard, situated at that part of the 

 junction of the stomach with the intestine, called the pylorus, 

 may be well exhibited. The insects named below will show 

 all these parts to advantage, and are, therefore, the best for 

 dissection : — 



Besides the parts of insects already alluded to, there are 

 other important organs that require a separate mention, such 

 as the ovipositors of various flies, the spinnerets of spiders, the 

 jaws of the locust, and other orthoptera, together with many 

 remarkable structures that will fall in the way of the minute 

 dissector. The insects in which the ovipositor can be weU 

 seen wUl be here enumerated, as well as some other parts of 



