Amongst a very large number of insects from the island Simalur, west of North Sumatra, received from Mr. Edw. Jacobson and collected by himself, the Papilionidae were represented by eight species, which are common and largely distributed. Two of them were each represented by a specimen, which prooved to be a new variety from that remarkable island. Comparing this material with that of the islands Nias and Sumatra, it seems to me that the fauna of these islands will differ the more and more from that of Sumatra, or that there is a strive after conformity. The following is an enumeration of the species received for the collection of the Leyden Museum.