Antennal regeneration in Daphnia magna

Antennal regeneration in Cladocera has been found to be rather variable. Przibram (1896, 1899) noted considerable variation both in amount and type of antennal regeneration in various species of Daphnia and Simocephalus. Kuttner (1913) found that antennal regeneration in Daphnia magna was extremely diverse. She noted that fully amputated segments never regenerated. Sciacchitano (1925) also pointed out that in Ceriodaphnia pulchella new segments of the antenna never formed. Setae were regenerated but never became as numerous, although often as large as the normal. Recently Agar (1930, 1931) published some extensive researches on antennal regeneration in Daphnia carinata and Simocephalus gibbosus. His data show that the degree of variation in the amount of regeneration was high in spite of the fact that he limited the amputation to a specific level on a certain segment in each species and that the experimental conditions were very well controlled.