Includes the articles "On Variation and Evolution in Planktonic Rotatoria by Bierger Pejler, "On the Larva of Siboglimum" by Gosta Jagersten. "Notes on the Littoriancean and Stenoglossan Genital Organs" by Johan Johansson, "Studies of Anabantid Fishes I, II, and III" by Sten Forselius.