The following is taken from he 1859 US Marine Corps regulations, detailing the clothing issue of a U.S. Marine in a four year period:
371. Allowances of clothing for an enlistment of four years, as follows:One uniform cap, two uniform coats, two sets of epaulette bullion, seven pairs of linen trowsers, eight pairs of woolen trowsers, twelve shirts, two stocks, sixteen pairs of shoes, one blanket, eight pairs of socks, eight pairs of drawers, four fatigue caps, four fatigue coats, eight blue flannel shirts, one great coat.372. After a guard marches on board of a sea-going vessel, each enlisted man shall be entitled to receive the additional articles of clothing following: one great coat (on charge, and only to be worn, under direction of Commanding Marine Officer in port, when the men are posted, or formed as a guard of honor on the quarter-deck: at all other times to be kept in the Marine Store-room; these extra coats to be worn, on post, by day only, in clear, cold weather), and two dark blue flannel sacks.
The following is a basic description of the uniforms worn by the enlisted Marine during the Civil War:
Federal Issue Kepi: The Marine Kepi, made of dark blue wool broadcloth, had a black patent leather visor and one small Marine button on each side of the cap. Attached to the front of the Kepi was a Marine bugle emblem made of brass with a white metal "M" placed over a red leather disc.
1859 Marine Frock Coat: The Marine Undress Frock coat was made of dark indigo blue kersey wool cloth and was lined in black polished cotton in the chest and front skirts. There was no lining in the sides or back. The frock coat had seven large Marine buttons on the front, two large Marine buttons on the back, and two small Marine buttons on each sleeve. The coat had a short stand up collar with one red welt along the bottom seam of the collar, there is no other piping on the coat. The skirt was to extend half way between the hips and the kness, and to be no shorter than the bottom of the crotch of the trousers.
Federal Issue regulation shirts: Regulations call for a wool flannel shirt of dark blue, to be worn with the dress uniform or during the winter with the undress uniform, and an un-dyed white linen military pattern shirt to be worn with the undress uniform, or in warm weather.
White Linen foot pattern trousers: Per the Marine regs these were to be worn from May 1st to October 14th (dates were subject to the commander's discretion). They had french pockets and a button fly front.
Sky blue foot pattern trousers: With a button style fly and french pockets. Per the regulations these were to be worn from October 15th until April 30th (dates were subject to the commander's discretion).
Period correct under-drawers: These were made of light materials such as cotton or linen.
Jefferson Brogans: Brogans were of black leather, smooth side or roughout. Metal heel plates and hob-nails were options with these shoes.
Socks: Were either wool or cotton.
1852 Marine Great coat: U.S. Marine great coats were blue-grey (AKA "cadet" grey) NOT sky blue and were not the same design and pattern as the Army regulation great coat. Marine great coats were single breasted with seven large Marine buttons on the front, and had a detachable cape which closed in front with five small Marine buttons.