11. The mantle is simple and forms a thin-edged flap over the branchial cavity. 12. In addition, this transcription factor plays an important role in limb and branchial arch development. 13. The mouth is located at the apex of the funnel, between the two branchial stalks. 14. The branchial plume is single ." 15. Both the openings of the branchial and atrial siphons possess lighter colored ridges on their rims. 16. Ostracods typically have no gills, instead taking in oxygen through branchial plates on the body surface. 17. The branchial syphon is large and surrounded by six large lobes; the cloacal syphon is small. 18. Their branchial ( or oral ) siphons are conical and positioned at the top of the body. 19. Protected within which are the branchial chambers which contain the respiratory organs of " Eurypterus ". 20. This siphonal opening also serves for the exit of the water that has entered by the branchial opening.
