ILLUSTRATIONS 



Xlll 



III. Bombus ruderatus yellow-banded queen, worker, and male. 



,, hortorum queen, worker, and male. To face p. 182 



,, latreill elites 



distinguendus ,, ,, 



IV. Bombus derhamellus queen, worker, and two males. 



,, sylvaricm queen, worker, and male. To face p. 192 

 ,, agrorum three queens, two workers, and two males 



of various colour patterns. 

 ,, helferanus queen, worker, and male. 

 ,, muscorum ,, 



V. Psithyrus rupestris queen and male. To face p. 206 



,, ves talis ,, 



, , distinctus , , 



,, barbutellus ,, 



,, campestris light queen, light male, and dark male. 



,, quadricolor queen, male. 



VI. Male armatures of all the British species of Bombus and 

 Psithyrus. p. 271 



All the specimens shown in the plates are British, except the 

 worker of Bombus soroensis, which is from the Caucasus Mountains, 

 and differs from British specimens in having the yellow on the 

 abdomen extending farther on the 1st segment. 



A millimetre scale is shown on page 154. 



