Hybrids between corn snakes and any other snake is very common in captivity, but rarely occurs in the wild. Hybrids within the genera Pantherophis, Lampropeltis, or Pituophis so far have been proven to be completely fertile. 
No history yet.
The head is dependent upon the Hybrid in question.
The body is dependent upon the Hybrid in question.
The belly is dependent upon the Hybrid in question.
The tail is dependent upon the Hybrid in question.
Most consider the majority of corns in the hobby to be hybrids, unless it is an actually lineage traced animal, with it being generally agreed that there is too much hybrid blood floating around in the corn snake gene pool to assume purity of any individual.
The prolific nature of external mutations in corns was able to happen in large part because the species that they originated in had a high degree of similarity, in both phenotype and physiology, to corns so the hybrids between them were not particularly unusual when viewed beside a normal corn. As such, specific “Corn Snake traits”, such as Ultra & Scaleless, originated from other snake species. 
Many different corn snake hybrids are bred in captivity. A few common examples include:
When hybrids of corn snakes are found in the wild, they have usually hybridized with other Pantherophis species whose ranges overlap with corn snakes.