How does a squid expel ink?

Squids are known for expelling ink as an escape mechanism (in addition to other aquatic creatures such as octopus and cuttlefish). Squids have ink sacs between their gills which produce/release the ink, then the ink can be dispersed more widely with a jet of water from the funnel (an organ near the mantle cavity that expels water). Squid ink is usually a blue-black color due to the melanin in it.

Two main ways of using ink as an escape mechanism have been observed. One, the squid can release a large diffuse cloud of ink (like a smokescreen) to obscure its predator's view and swim away quickly. Two, the squid can also release several pseudomorphs (smaller cloud of ink that holds its shape longer) that are about the same size/shape as the squid, deceiving the predator into attacking the pseudomorphs instead while the squid escapes.