TELUST RATIONS xiii 
III. Bombus ruderatus—yellow-banded queen, worker, and male. 
»  ortorum—aqueen, worker, and male. To face p. 182 
» ¢atreillellus a Bs 
as distinguendus or 33 
IV. Bombus derhamellus—queen, worker, and two males. 
»  sylvarum—aqueen, worker, and male. To face p. 192 
»  a@grorum—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 
$5 vestalis 5 
BA aistinctus ys 
<5 barbutellus s 
53 campestris—light queen, light male, and dark male. 
of guadricolor—queen, male. 
VI. Male armatures of all the British species of Lombus and 
Psithyrus. ps 271 

All the specimens shown in the plates are British, except the 
worker of Bombus soroénsts, which is from the Caucasus Mountains, 
and differs from British specimens in having the yellow on the 
abdomen extending farther on the Ist segment. 

A millimetre scale is shown on page 154. 
