Carl Johannes With (11 December 1877 – 16 June 1923) was a Danish medical doctor and arachnologist, specialising in pseudoscorpions and mites.[1][2]
With was born in Lemvig to Nicolai Rasmus With and his wife Rasmine Sophie Dorothea With, but was orphaned by the age of five.[2] With married Inge Kiørboe on 1 July 1909, and together they had three children.[2] With died in 1923 in Skibstrup, in the parish of Hellebæk (Helsingør Municipality),[3] while still working on a dissertation on lupus.[2]