Two collaborating naturalists of the 19th century A naturalist and collector Dominik Bilimek (portrait 1864; by courtesy of Fototeca dei Civici Musei di Storia ed Arte Trieste, Italy; inventory no. 4738R) B the only preserved portrait of Heinrich Hauffen (Digitalna knjižnica Slovenije, also: Digital Library of Slovenia, reference number 5S74D58Z, Ilustrirani Slovenec) C drawing of Carychium reticulatum from the H. Hauffen (1856b) manuscript (Archiv NMS, leto 1856, št. 47) D drawing of Carychium bidentatum from locality Glaven verh; H. Hauffen (1856b) manuscript (Archiv NMS, leto 1856, št. 47).