ERROR:HDLParsers:164 - "C:/.Xilinx/Counter/Main.vhd" Line 35. parse error, unexpected ENTITY, expecting COMMA or SEMICOLON

I don't know what error it pointing out... I am not able to see what it means, could someone clarify it for me.. 

```
----------------------------------------------------------------------------------
-- Company: 
-- Engineer: 
-- 
-- Create Date:    23:52:28 03/05/2014 
-- Design Name: 
-- Module Name:    Main - Behavioral 
-- Project Name: 
-- Target Devices: 
-- Tool versions: 
-- Description: 
--
-- Dependencies: 
--
-- Revision: 
-- Revision 0.01 - File Created
-- Additional Comments: 
--
----------------------------------------------------------------------------------
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL
-- Uncomment the following library declaration if using
-- arithmetic functions with Signed or Unsigned values
--use IEEE.NUMERIC_STD.ALL;

-- Uncomment the following library declaration if instantiating
-- any Xilinx primitives in this code.
--library UNISIM;
--use UNISIM.VComponents.all;

entity Main is
PORT(
        CLK: in std_logic;
        LED: out std_logic_vector (7 downto 0)
        );

end Main;

architecture Behavioral of Main is
signal counter: std_logic_vector (7 downto 0);
signal prescaler:  std_logic_vector( 22 downto 0);
begin

CounterProcess: process(CLK)
begin
if rising_edge(CLK) then
    if prescaler < "1111111111111111111111" then 
        prescaler <= prescaler + 1;
        else
            prescaler <= (others => '0'); 
            counter <= counter + 1;
    end if;
end if; 
end process;

LED <= counter; 

end Behavioral;

```