August Johann Rösel von Rosenhof the fathers of German entomology. The fourth part is practically a monograph of the spider Araneus diadematus. The description of the animal is illustrated by six plates which show the differences in variation of the colouring of the species. They show also internal dissections. Rosenhof was interested in the production of silk but he confused the anus with the opening of silk-producing glands. He published, between 1753 and 1758, "Historia naturalis Ranarum nostratium" devoted to frogs. The quality of the work, in particular of its illustrations, make it one of the most beautiful devoted to these animals. He presented the
European perch European perch Perca fluviatilis, commonly known as the European perch, perch, redfin perch, big-scaled redfin, English perch, Eurasian perch, Eurasian river perch or common perch, is a predatory species of perch found in Europe and northern Asia. The species is a popular quarry for anglers, and has been widely introduced beyond its native area, into Australia, New Zealand, and South Africa. They have caused substantial damage to native fish populations in Australia and have been proclaimed a noxious species in New South Wales. European perch are greenish with red pelvic, anal and caudal fins. They have five to eight dark