Velella sentence example
- In Velella the pneumatophore becomes of complex structure and sends air-tubes, lined by a chitin and resembling tracheae, down into the compact coenosarc, thus evidently serving a respiratory as well as a hydrostatic function.
- In their most primitive form they are seen in Velella as " gonosiphons," which possess mouths like the ordinary sterile siphons and bud free medusae.
- Thus in Velella free medusae are produced, which have been described as an independent genus of medusae, Chrysomitra.
- In forms with a compact coenosarc such as Velella, Physalia, &c., the separate cormidia cannot be sharply distinguished, and such a condition is described technically as one with " scattered " cormidia.
- 69) and its allies; and (3) Velellidae, represented by the well-known genus Velella (figs.Advertisement
- - Upper sur- sisting of a bract, siphon, tentacle and face of Velella, showing gonophore; when free it is known as pneumatophore and sail.
- - Diagram of the structure of Velella, showing the central and peripheral thirds of a half-section of the colony, the middle third being omitted.