The head should be expressive with a broad forehead, large eyes, with a straight or slighly dished face, and large nostrils.
The body should be compact with a short back, close coupling, broad loins, well sprung ribs, croup long and well muscled, with tail attached high, carried gracefully and straight.
The legs should be straight and sound with short cannons, flat bone and an appearance of over all substance with refinement.
Other distinctive attributes of the Morgan horse are his presence and personality. 

These include:
Animation, stamina, vigor, alertness, adaptability, attitude and tractability.
Breed Standards for the Morgan Horse