Phylosian ships were a type of interstellar space ship utilized by the Phylosians.
In 2269, the Phylosians intended to launch a fleet of these vessels from their homeworld of Phylos to impose peace in the galaxy following their encounter with Stavos Keniclius 5.
Upon their discovery on Phylos, Captain Kirk theorized these ships to be "a technology possibly greater than anything we 'animal' species [have created]." Doctor McCoy noted that the ships, which were covered in vines, never got off the ground, as a result of the great plague that affected their people, and wondered aloud what their intended purpose was before they became a more peaceful people.
It was later revealed by Agmar, that their fleet's intended purpose coincided with Keniclius's, to "carry out [their] own plan to impose peace on a galaxy that knew none." Ultimately, the fleet remaimed grounded, as the Phylosians, with the assistance of Keniclius 5 and Spock 2, could focus on rebuilding their own society. (TAS: "The Infinite Vulcan")
The script describes these ships as " a fleet of translucent year drop-shaped space ships hundreds of feet high."