330 GENERAL ZOOLOGY 



The queen's sting is larger than that of the worker, with fewer and 

 smaller barbs on the darts. The poison sac is large. 



It is well established that the sting of the honeybee is a modi- 

 fied ovipositor and is an example of a complete change in function 

 of an organ. An ovipositor is a structure developed at the end 

 of the abdomen of the female of many insects. It is used for 

 making holes in leaves or in stems, in which the eggs are laid. 

 Grasshoppers make holes in the ground for the eggs. Among 

 the Hymenoptera, the group to which the honeybee belongs, it is 

 only forms like bees and wasps that are provided with stings. 

 The females of other Hymenoptera have ovipositors which closely 

 resemble those of such insects as the katydids, crickets, cicadas, 

 and the grasshoppers. Figure 185 shows the ovipositor of a 



common grasshopper. Since the queen 

 honeybee deposits her eggs in wax cells 

 prepared by the worker, it can be under- 

 stood why the ovipositor should no longer 

 function as such. That it develops into 

 Fig. 186.— Abdomen Tf a piercing organ is in keeping with the 

 the grasshopper showing the f ac t that the parasitic Hymenoptera use 

 ovipositor, o. the ovipositor t0 insert eg g S into the 



bodies, eggs, or nests of other insects. The absence of a sting 

 in drones is understandable since the forerunner of the sting 

 was primarily a female organ. 



The fangs of a rattlesnake are another example of a weapon, 

 quite different from the sting of the bee in structure and develop- 

 ment and yet functionally of the same general significance. The 

 timber rattlesnake, Crotalus horridus, is provided with a pair of 

 erectile fangs surrounded by a fleshy sheath and located in 

 the front of the upper jaw. Each fang is hinged at its base to the 

 maxillary portion of the jaw, so that it can be folded back into the 

 sheath when the mouth is closed. The fang is a hollow tooth, 

 the channel extending from the base of the tooth to a point near 

 the sharp end. At the base of the tooth, the channel connects 

 with the duct of a poison gland, located at the side of the upper 

 jaw (Fig. 186). In striking, the fangs are buried in the victim 

 and the poison is injected into the wound. A rattlesnake does 

 not always coil and rattle before it strikes, although the power 

 of the blow is undoubtedly increased when delivered from the 

 coiled position. The poison of the timber rattlesnake is highly 



