An organic grenade or quill-grenade was a green, somewhat sticky biological globule which was fired from a Xindi grenade launcher. The globule very briefly pulsated before shooting out a barrage of projectiles, sharp quills which were green with yellow heads and which could painfully shoot down Humans.
In 2153, an organic grenade was deployed by a Xindi-Reptilian member of a boarding party that invaded Enterprise NX-01. The darts from the organic grenade shot down a group of Starfleet security officers who were guarding imprisoned Oran'taku Rajiin in the ship's brig. (ENT: "Rajiin")