• With few exception ectoprocta are hermaphrodite. Usually one ovary, sometimes two and one or more testes are found within same individual. Gonads develop on the peritoneum of body wall.
• The ovary is located distally towards the oral end or about the middle and testes generally proximally towards the base. The ovary consists of a cluster of rounded oocytes with large nuclei enclosed in the thin peritoneum.
• Often ovary and testes mature at different time tendency of protandary is not uncommon. The ripe ova escape into the coelom where fertilisation takes place.
• The supraneural pore is a simple aperture between the mouth and base of tentacles. They communicates with lophoral coelom with exterior and serve for exit of eggs and probably also of sperms. Cross fertilisation is wide spread among the bryozoans.
• More often early fertilisation takes place under the protection of parents
• Brooding chamber makes place in the coelom or in special diverticulum of it serving as a brood chamber. Other structure serve as a brood chamber may be tentacular sheath.
• Larvae cleavage is holoblastic and approximately equal. A coeloblastula results which gastrulates by delamination at the vegetal pole leading to modified trochophore larva.
• The larva varies considerably in forms. It is bell shaped looking triangular in side view but is strongly compressed laterally. It is encircled by ciliary girdle or corona, forming a thickened edge. It is chief locomotory organ of larva and it divides the surface into two distinct regions oral and aboral. The aboral surface is enclosed in bivalve shell at aboral apex there is an opening between the two valves through which it projects knob like ciliated retractile disc, apical organ or calotte. It is carried forward in swimming. The anterior end of ciliary cleft usually bears a tuft of cilia called vibratile plume.
• The posterior invagination of thickened ectoderm is adhesive organ or the sucker by which larva attaches itself.  In between the pyriform organ and adhesive sac lies a spacious non ciliated cavity, or vestibule at bottom of which is the mouth.

Metamorphosis

• The larva attaches itself by the ventral adhesive sac which is suddenly spread out over the substrate as a flat disc of ectoderm. The two shell valves are shed and alimentary canal is disappears in fact all larval organs undergo histolysis so that the larva becomes reduced in a layers of epithelium surrounding a loose mass of cells and debris. The ectoderm secretes outer cuticles.
• The aboral ciliated disc begins to proliferate and invaginates inward to form vesicle or primordium of polypide. The vesicle is surrounded by mesenchyme, which gives rise to peritoneum organs of mesoderm of the future polypide. The ectoderm of vesicle also contribute to the mesoderm beside forming the lining of alimentary canal, the ganglion covering of the tentacles and the tentacular sheaths, etc. The primary zooids also called ancestrula thus formed gives rise to future colony of asexually budding.