Jonas sometimes also published as "J." H. Jonas. He studied, together with
Wilhelm Dunker, the "Museum Gruneri", a large collection of species in the bivalve family
Pteriidae. This study was published as
Verzeichniß der Conchyliensammlung des verstorbenen Herrn Consul Gruner, welche im Ganzen verkauft werden soll von Bunsen Hausschild 1857. Bremer Druck 1857. In 1846 Jonas described the "Rodatz collection". Rodatz collected many mollusks during a number of commercial expeditions from Germany to
Zanzibar and
West Africa in the period of 184351, and from the
Red Sea in 1845. He had offered his specimens to . ==References==