124 



SMITHSONIAN MISCELLANEOUS COLLECTIONS 



(fig, 41, 2VI) is sometimes called the sheath of the sting (Cheshire, 

 1886, Snodgrass 1910, 1925), or the shaft (Betts, 1923) ; but, since 

 this part is hollowed beneath to form a channel giving passage to the 

 poison, European writers generally term it the sting trough, or gutter 

 (Stachelrinne, f ourrou- guttler e) . The enlarged basal part of this 

 organ is the bulb {bib) ; the slender tapering distal part we may term 

 the stylet (stl). The third valvulae (figs. 40, 41, jVl) are sometimes 

 called the " palpi " of the sting, but since their chief function is, as in 

 other Hymenoptera, to ensheath the distal part of the sting or oviposi- 

 tor shaft, they are better termed the sheath lobes (Stachelscheiden) , 

 The general structure of the bee's sting differs but little from that 

 of the ovipositor of other Hymenoptera, and it is only in certain de- 



FiG. 41. — The sting and associated parts of Apis meHifica, worker. (From 

 Snodgrass, 1910, but relettered in accord with the general nomenclature of the 

 ovipositor adopted in this paper.) 



tails that the sting is specialized for its specific function of ejecting 

 the poison liquid from the reservoir of the poison gland. 



The spiracular plates of the eighth tergum overlap externally the 

 upper ends of the lateral plates of the ninth tergum (fig. 40). The 

 spiracular plates of the worker are triangular in shape (fig. 43 B, 

 Lsp), with the lower anterior angle of each produced into a process 

 for muscle attachment. In the queen the plates are relatively larger 

 and of irregular form (fig. 44 C). Though the spiracular plates are 

 connected entirely by membrane with the surrounding parts, they 

 have an elaborate musculature, which will be fully described later, 

 but it should be noted particularly that they are anchored in position 

 by dorsal muscles from the seventh tergum and ventral muscles from 

 the seventh sternum (fig. 43 B). On the other hand, each spiracular 

 plate is connected with the ninth tergal plate of the same side by two 



