Some time ago Mr. P. J. Buitendijk, who enriched our collections already with many valuable objects, presented to our Museum three excellently preserved specimens of a Cubomedusa, belonging to the genus Chiropsalmus. As far as I know, hitherto only two species of this remarkable genus are described, viz. Ch. quadrumanus (Tamoia quadrumana), observed by Fritz Müller in the sea near Santa Catharina (Brazil)¹), afterwards also found by Wilson near Beaufort (North-Carolina)²) and Ch. quadrigatus, based by Häckel upon a single specimen, that was collected by Thallitzer at the coast of Rangoon ³). Unfortunately the last specimen was in an indifferent state of preservation, so Häckel was unable to give a detailed description of it ; nevertheless I think it elaborate enough to conclude, that our individuals belong to another species, that, in honour of its discoverer, may be named Ch. Buitendijki. Like the specimens of Chiropsalmus quadrumanus those of Ch. Buitendijki were met with in the vicinity of the shore, in the road of Batavia; they have no colour, but are transparent, gelatinous, the tentacles only have a rosy hue.