No, they did not come on the Mayflower, but Plymouth Rock chickens have been around in New England since the mid 19 century. Created as a dual purpose (for eggs and meat) bird, Plymouth Rocks make a great small farm or backyard bird. They are calm, easygoing, and generally lay eggs at an above average rate.
Plymouth Rocks have several different coloring schemes, but the most popular is the black and white barred pattern. For this reason, many Plymouth Rocks are called Barred Rocks, and you will also hear the term Barred Rock applied to this entire breed. However, there are white, buff, black, silver, and other colors of Plymouth Rock chickens that do not have the full barring pattern and probably should not be called Barred Rocks.
Here is a picture of a Barred Rock hen. You can see a little Eglu coop in the background.
Plymouth Rock (Barred Rock) Facts
Hens range from 6.5-7.5 pounds, making them one of the heavier breeds.
Barred Rock: Black and white bar pattern with bright red combs and wattles.
Partridge: The partridge variety is dark red with a copper colored collar and some black feathers on the edges.
White (all white), black (all black), and several other color schemes exist as well.
Very good egg layers (average about 4 per week), which are large and brown.
Calm, docile, easygoing.
It seems that some strains of Rocks are better layers than others. All are dependable, but some approach excellence in this department. Try to find out if yours comes from a good line with a productive history.