public Viruses() {
		// Initialize the list of all possible virus choices.
		viruses = new Virus[] {
				//new BlackVirus(),
				new BlueVirus(),
				new CyanVirus(),
				new DarkGrayVirus(),
				new GreenVirus(),
				//new LightGrayVirus(),
				new MagentaVirus(),
				new OrangeVirus(),
				new PinkVirus(),
				new RedVirus(),
				new YellowVirus()
		};
		// Shuffle randomly.
		int num = viruses.length;
		for (int i = 0; i < num; i++) {
			int randomPos = (int) (Math.random() * num);
			Virus temp = viruses[i];
			viruses[i] = viruses[randomPos];
			viruses[randomPos] = temp;
		}
		// Reduce to a set of viruses of the specified size.
		int virusCount = ViralSpread.getVirusCount();
		if (virusCount < viruses.length) {
			Virus[] tempViruses = new Virus[virusCount];
			for (int i = 0; i < virusCount; i++)
				tempViruses[i] = viruses[i];
			viruses = tempViruses;
		}
	}