17. BOMBUS MUSCORUM, Linnzus. 
Large Carder-bee. 
Synonyms :—venustus, Smith, this also includes 2. helferanus ; 
cognatus (Stevens), according to Schmiedeknecht ; smithianus, 
White. 
QUEEN.—Slightly larger than 5. agrorum and B. hel- 
feranus ; length 18-19 mm., expanse 33-35 mm. 
The colouring has hitherto been supposed to be indis- 
tinguishable from that of B. helferanus, but after having 
bred and compared many examples of each species, I 
notice that the following differences are constant, and it 
will probably be found that they are sufficient for identi- 
fication in every case. 
The orange-brown on the thorax never has any black hairs 
mixed with it; in agrorum and helferanus black hairs are 
frequently present. 
In specimens from England the orange-brown on the 
thorax is more or less encroached upon from in front and from 
behind by very pale yellow, this colour in immature 
specimens being almost white, and in faded ones pale 
brown ; this is the variety s/adenz of Vogt. But in speci- 
mens from Scotland there is little or no encroachment of 
pale hairs, and the orange-brown is slightly redder than 
in the south of England; this is the variety pallzdus of 
Evans. 
The abdomen is slightly yellower than in helferanus. 
The brown band on the 2nd segment and the fainter one on 
the 3rd segment are much lighter and more diffuse than in 
helferanus, in fact they are usually only faintly discernible ; 
in perfectly fresh specimens they are often of a beautiful 
brownish lemon colour which is very evanescent and soon 
fades to pale brown. The hairs on the 2nd segment look 
darker than they really are on account of their erectness. 
The coat is slightly longer, slightly more even, and 
slightly denser than in /e/feranus, and denser and more 
even than in agrorum. In specimens from the south of 
