The Mollusks recorded in this paper, have been collected by Mr. J. W. van Nouhuys on Taliabu, one of the larger Xulla-isles, and were presented by him to the Leyden Museum of Natural History, together with a few other species from various localities, amongst which latter are however no new species. As the only record of Mollusks from the Xulla-isles is that of Xesta citrina var. by Wallace, mentioned hereafter in my note on X. halmaherica, I thought it would be interesting to enumerate them all, instead of describing only the new forms. I think the number of species existing in that island will not be exhausted by these 17 species, the more so as the second part of the collection contained several species not represented in the first lot, but the number seems to be important for a locality the molluscan fauna of which was nearly quite unknown. 1. Xesta halmaherica (Strubell) Kobelt.