viii DISTINGUISHING THE SPECIES 145 



spring while the workers and the males do not 

 begin to appear until the approach of summer. 



The skin of the humble-bee is black, so that all 



fore winy 



antenna 



HEAD 



hind winy 



base of abdomen 



corbie uta or pe 



metatarsus 



tarsi 



fort lea- 

 middle le 



QUEEN 



flagellar* 



hind ten 



ABDOMEN 



apex of abdorne-n 



3 ocelli or simple eyes 



scape 4"~*%^JrC^ e y e 

 5 



clypeus 



tnandiile 

 or J a w 



maxilla 



labial 

 palpi 



Armature of Male 



Fig. 25. External anatomy of Bombus ruderatus. 



Head of 

 Queen 



colour is in the coat, but in some of the species the 

 feet are more or less testaceous. 



The colour patterns of the coat on the upper 

 surface of the body differ more or less in each 

 species, and generally afford the readiest means of 

 distinguishing one species from another. But in 



