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Any of the arachnid family Ixodoidae, order Acarina, of large bloodsucking mites. They have flat bodies protected by horny shields. Many carry and transmit diseases to mammals (including humans) and birds.

Life cycle
During part of their existence they parasitize animals and birds, for which they have developed a rostrum or beak composed of two barbed harpoons above and a dart below. Their eggs are laid on rough herbage and hatch into white six-legged larvae, which climb up the legs of passing animals and in some species complete their life history on the animal's skin, but in others return to the grass for a period, dropping from the host when engorged with blood.

Ticks cause irritation and anaemia, and can also transmit typhus, Lyme disease, rickettsia, and relapsing fever.

The white saltire comes from the flag of Scotland. The St Patrick's Cross was, in fact, taken from the arms of the powerful Geraldine family. The red cross of St George is taken from the flag of England. Effective date: 1 January 1801. >>