Bee with bumps/lumps

Bee with bumps/lumps

Observation - Bee with bumps/lumps. Description: Bee (I doubt the photo is good enough to ID the actual bee though I think its a Buff Tailed Bumblebee) its the spots/lumps just behind the head that I'm most curious about

Bee (I doubt the photo is good enough to ID the actual bee though I think its a Buff Tailed Bumblebee) its the spots/lumps just behind the head that I'm most curious about