In certain star-fishes, small depressions in the layer of pigment which surrounds the nerve are filled, as described by the author just quoted, with transparent gelatinous matter, projecting with a convex surface, like the cornea in the higher animals.
Zenbait itsasizarretan, nerbioa inguratzen duen pigmentu-geruzako sakonune txikiak, aipaberri dugun autoreak deskribatzen duen moduan, gai garden gelatinatsu batez beterik daude, eta hau azalera konbexu bat formatuz irtetzen da, goragoko animalietan kornea bezala.