Fig 4. Medusae production of Carukia barnesi.

I. Initial stage of medusae production, note the change in shape of the hypostome region. II. The tentacles migrate to four opposing sections of the forming bell, fuse, and begin to form the rhopalia. III. The bell begins to pulse and a narrowing divides the bell of the forming medusae from the hypostome of the original polyp. IV. The remaining polyp after completed medusae production. V. Oral view of a newly detached medusa. VI. Lateral view of a newly detached medusa with pigmented nematocyst batteries on the bell. Letters indicate: a) change in shape of the hypostome region; b) fusing of tentacles which begin to form rhopalia; c) early development of medusa tentacles; d) polyp producing a medusa through monodisc strobilation; e) connective tissue between the polyp and forming medusa; f) pulsing medusa approximately 24 hours prior to detachment; g) hypostome; h) feeding tentacle; i) formed rhopalia; j) short feeding tentacles.