Cornish X Feathers?

[hoosierchicken]

Hello , I have 25 cornish x . They never have gotten all their feathers on thier back and under wings. They have litlle feather pins that havent got bigger. Other feathers look OK. Is this due to hot weather or ? Have you seen this before? They are 7-8 weeks old.
Thanks BG

 

[FisherMOM]

That's the way that they are. They are homely looking things for a long time. Over night, it seems, they get feathers.