A Bumblebee on Lavender, look closely and on her head between the two black antennae, you can see a thicker blackish/brown tube. This is her Proboscis, a sort of mouth part that in some insects has become elongated and acts like a tube through which to suck up their food. Nectar in this case.
The Proboscis can be drawn back into the Bees body when not in use.