Need help telling difference!

[Feathers Acres]

I have Barred rocks, polishes, and cochins and they all pretty much lay the same colored eggs, brown.

Is there anyway I can tell apart the cochins eggs from the other eggs?

 

[skand]

umm, not sure, are they different shades of brown? Maybe you can keep track that way? Just pencil in the name when you catch whoever layed? Or even sizes?

 

[The Chicken Lady]

I was thinking that the Cochins' eggs might be smaller than those laid by the Barred Rocks.