Why is physalia called portuguese-man of war?

Explanation

**Step-by-Step Solution:**

1. **Understanding Physalia**: Physalia, commonly known as the Portuguese Man-of-War, is a marine organism classified under the phylum Cnidaria. It is important to recognize that it is not a single animal but a colonial organism made up of specialized polyps.

2. **Structure of Physalia**: The most notable feature of Physalia is its gas-filled bladder, also known as a pneumatophore. This bladder allows it to float on the surface of the water.

3. **Appearance from a Distance**: When viewed from a distance, the gas-filled bladder of Physalia resembles the sails of a ship. This resemblance is particularly striking when the organism is floating on the water's surface.

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