Among the notes and collections that came to the Zoological Museum, Amsterdam, after Dr H. C. REDEKE’s death in 1945, I found an entirely completed manuscript, dealing with a new D’Arcythompsonia found in a canal at Den Helder (Netherlands). This is the species cited as nomen nudum by KARL LANG (1948, p. 274), in his “Monographie der Harpacticiden”. Pencil drawings and two coloured pictures relating to this species were found among REDEKE’s papers. They have been redrawn in China Ink, without important alterations. The original slides used for these illustrations were found among the temporary glycerin mounts of Dr REDEKE; they are now — in a rather bad condition of course — in the Zoological Museum, with the collection number Co. 105,002. The holotype ♂ (Z.M.A. coll. no. Co. 105,000) and allotype ♀ (Z.M.A. coll. no. Co. 105,001) were selected from a vial labelled in REDEKE’s handwriting “D’ Arcythompsonia neglecta n.sp.”