APIS MELLIFICA. 173 



the muscles attached to the plates continue active, and the sting 

 works deeper and deeper in. Understand why it works in instead 

 of out. 



2. Lying near the base of the shaft is a large poison sac or 

 reservoir, which is very muscular. It receives its poison from 

 the poison gland, a long and narrow coiled tube that is bifurcated 

 near its free end. It discharges the poison by means of the 

 contraction of the muscles of its walls through a rather large, 

 short duct into the space inclosed by the sheath and the two 

 barbs. Each barb bears a prominence that serves as an injector, 

 which moves backward and forward with the barb to which it 

 is attached, in an enlargement of the basal portion of the sheath. 

 It may be seen in the preparation. In this way poison is forced 

 into the wound. Poison may also be admitted to the cavities 

 of the lancets, which are hollow, and escape through minute pores 

 near the barbs. 



3. Lying near the base of the shaft of the sting, sometimes 

 covered by the poison sac, may nearly always be found the last 

 pair of abdominal ganglia, from which nerves may be traced to 

 the muscles that are attached to the plates. 



Understand the whole mechanism, how it is operated and 

 its use. 



4. Catch a living bee by the wings and press the end of the 

 abdomen against a piece of soft leather, such as a leather-covered 

 book. Pull the bee away and with a lens watch the movements 

 of the sting, which will remain in the leather. Observe the 

 spasmodic contractions of the poison sac. See how long and how 

 energetically the movements are continued and how deep the 

 sting is worked in. This should remind you that a sting should 

 be removed immediately, and that it should not be pulled out, 

 as grasping the poison sac will aid in injecting the poison, but 

 scraped off with a finger-nail or some other instrument. 



A drawing showing the mechanism of the sting is desirable. 



Field: A Study of an Ant. Proc. Acad. Nat. Sci., Philadelphia, 1901. 

 Phillips: A Review of Parthenogenesis. Proc. Am. Phil. Soc., 42, 1903. 

 Root: A, B, C, and X, Y, Z, of Bee Culture. 



