. y-Prdist Text-fig. 31. Knee-shaped bracts of a species of Forskalia from 'Discovery II' St. 1585, 1400-700 m., x 15. Of the above bracts, five are similar (Text-fig. 31) in having a concave oval facet on the dorsal side, a cavity on the ventral side, a convex facet at right angles to the dorsal one, a three-cornered lateral process with a ridge and a canal that has a right-angled bend in the middle of its course. All the bracts are somewhat hollowed on one side and have a distal process, triangular in section, on which the canal ends. The knee-shaped bracts described above can be mirror imag
. y-Prdist Text-fig. 31. Knee-shaped bracts of a species of Forskalia from 'Discovery II' St. 1585, 1400-700 m., x 15. Of the above bracts, five are similar (Text-fig. 31) in having a concave oval facet on the dorsal side, a cavity on the ventral side, a convex facet at right angles to the dorsal one, a three-cornered lateral process with a ridge and a canal that has a right-angled bend in the middle of its course. All the bracts are somewhat hollowed on one side and have a distal process, triangular in section, on which the canal ends. The knee-shaped bracts described above can be mirror images of each other, as the figures show. At present we do not know enough about the morphology of species of Forskalia to be able to identify species from loose bracts and nectophores, unless they are of living Mediterranean specimens. CALYCOPHORAE Post-larvae of Prayidae and Hippoppdiidae It has long been recognized that Prayids and Hippopodiids more nearly resemble one another than either resembles the remainder of the Calycophorae. In both of the families there appears to be a similar larval, caducous nectophore, combined possibly with a bract, like the one first figured by Chun (1888 a) for the Canary Islands Hippopodius hippopus. Up the present time we have known very little about the larvae of any Prayid or Hippopodiid species, and as far as I am aware no one has succeeded in breeding any except Metchnikoff (1874). Eighty years ago he reared some larvae of H. hippopus at Villefranche, but could not keep them alive for more than ten days. The rest of our knowledge is based on larvae of unknown parentage captured in the sea. Great caution should be used in accepting identification of such larvae unless there is within the hydroecium a young, definitive nectophore of recognizable shape.
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