Epithel. cells always need a layer to grow on Original young polypide from septal wall wh. becomes Regeneration of [illegible] of zooidal possible outer wall? Regen polypide from any wall of tentac sheath. Ostium off, Pergens etc. argument about wh. one of them was seeing what - they were all correct but disagreeing w. each other in semantics Cyphonaute 3 layers - ectoderm mesodl. Tentoder but in Membranophora wh. is a delayed form these layers are not clear -- mesoderm. 1 2 pushing down where blastopore is to give 3. 3 4 + holes disappear. cemento epithelium joins After stage 3, cementing of central part followed by epithelium of 2 lateral horns joining central part to form 2 c.ve. holes wh. then are enclosed & disappear.