The Validity of Cnidonema Vallentini as a Species.
The writer agrees with Gilchrist (1919) that the crawling or walking medusae of the Southern Hemisphere constitute a different genus (Cnidonema) from those of the Northern Hemisphere (Eleutheria). Therefore, for the reasons given above, the type species of the Southern Hemisphere becomes Cnidonema vallentini Browne. In 1911 Vanhöffen considered the Southern species charcoti and hodgsoni together with the new specimens he found at Kerguelen as identical with the type species C. vallentini. Gilchrist (1919), however, considers it wiser to keep C. charcoti and C. hodgsoni as separate species and. adds Vanhöffen's Kerguelen specimens as a new species C. kerguelense. Gilchrist (1919) describes Cape of Good Hope specimens as C. capensis n.sp. Briggs (1920) considers as valid all the
Fig. 1.—Juvenile medusa just liberated from the parent hydroid.
Fig. 2.—Juvenile medusa exumbrella surface.
Fig. 3.—Exumbrella surface, mature medusa, with gonads.
Fig. 4.—A. Tentacle form of medusa with up to 18 tentacles. B. Tentacle form of medusa with more than 18 tentacles.
Fig. 5.—Exumbrella surface of adult medusa present in aquarium tank over a period of years.
Fig. 6.—Exumbrella surface of adult medusa from Island Bay, Wellington.