CONTINENTAL MARINES FLAG

The Gadsden flag is a historical American flag with a yellow field depicting a rattlesnake coiled and ready to strike. Positioned below the snake is the legend "DONT TREAD ON ME". The flag was designed by and is named after American general and statesman Christopher Gadsden. It was also used by The United States Marine Corps as an early motto flag.

In fall 1775, the United States Navy was established to intercept incoming British ships carrying war supplies to the British troops in the colonies. To aid in this, the Second Continental Congress authorized the mustering of five companies of Marines to accompany the Navy on their first mission. The first Marines that enlisted were from Philadelphia and they carried drums painted yellow, depicting a coiled rattlesnake with thirteen rattles, and the motto "Don't Tread On Me." This is the first recorded mention of the future Gadsden flag's symbolism.

http://en.wikipedia.org/wiki/Gadsden_flag

CONTINENTAL NAVY FLAG

In the autumn of 1775, as the first ships of the Continental Navy readied in the Delaware River, Commodore Esek Hopkins issued, in a set of fleet signals, an instruction directing his vessels to fly a "striped" jack and ensign. The exact design of these flags is unknown. The ensign was likely to have been the Grand Union Flag, and the jack a simplified version of the ensign: a field of 13 horizontal red and white stripes. However, the jack has traditionally been depicted as consisting of thirteen red and white stripes charged with an uncoiled rattlesnake and the motto "Dont Tread on Me"

http://en.wikipedia.org/wiki/First_Navy_Jack

CONTINENTAL PRIVATEER FLAG

One of the examples given in the book of an American revolutionary flag with stripes other than red and white is that of an unidentified American privateer, which "sported a black and yellow striped ensign. While at Martinique in 1776 the brig Reprisal flew a similar flag of yellow and white."