Amsterdam: C. G. Ven der Post, 1857. Octavo, four uncoloured folded lithographic plates. binder's cloth, paper title on spine, library stamps, scarce.

The Harbor Seal (Phoca vitulina) is a true seal found along temperate and Arctic marine coastlines of the Northern Hemisphere.

Willem Vrolik (1801-863) was a Dutch anatomist and biologist. He wrote and important monograph on Tree Kangaroos.