Large swollen lump on one side of Hen's neck - Not the Crop - Any Ideas please?

[LBFarms]

I have a year old barred rock hen with a large round swollen spot on the left side of her neck, just below the jaw, It is exactly where the red spot is, behind and under the eye. It is NOT her crop. None of the other chickens have this. Don't know about her behavior, other than she is in the nest box tonight rather then on the roost like she usually is. I need to to know how to treat this.

 

[TeamChaos]

What is the texture of the lump like? Does it have any sort of scab or scratch that would indicate it is an infection?

 

[LBFarms]

It is not real hard, I can push in on it some. No scabs or scratches or anything like that.

 

[LBFarms]

Bump

 

[TeamChaos]

Weird. Can you feel the "back" of it? In other words, is it like a free floating marble in there or does it feel connected?