As part of an ongoing study, which is almost finished, I've been measuring shells of several species of Discus. Among the species included in the study is the European Discus ruderatus. Here are the labels of 2 old lots from the Carnegie Museum of Natural History in Pittsburgh.
The oldest date I can make out on the labels is 7/30/01; undoubtedly, that was 1901. And the stated location "Klausenberg, Transylvania, Hungary" was presumably the city of Cluj in Romania.
The 2nd lot was collected in Grisons, a canton in Switzerland, in August 1852.
The previous post in this series was about Discus rotundatus.