Nereis buitendijki n. sp. Malacca-strait. P. Buitendijk, 1910. Amidst the Plankton of Malacca-strait Mr. P. Buitendijk met with a small Nereis-specimen, characterized by the presence of a digitiform appendage on the dorsum of the parapodia in the posterior body-region. The worm measures about 14 mm. in length. The head is longer than broad, trapezoidal, provided with large, broad palps and two short antennae, measuring about a third of the length of the head. The tentacular cirri are rather short, the longest of them reaching about to the 6th segment. The armature of the proboscis consists of: I = 2 paragnaths, one behind the other. II = an oblique, distichous group of 10 paragnaths. IV = a transverse, tristichous group of 10 to 12 paragnaths. III = 3 paragnaths, arranged in a tri- Fig. l. angle. V = o. VI = a round group of 10 to 12 paragnaths. VII—VIII = a subtristichous belt of paragnaths. A parapodium of the anterior body-region consists of an elongated,