Correns was a student of Karl Nägeli , a renowned botanist with whom Mendel corresponded about his work with peas , but who failed to understand how significant Mendel 's work was .
By a quirk of history Correns was a student of Nägeli , a renowned botanist with whom Mendel corresponded about his work with peas . Nägeli failed to understand how significant Mendel 's work was .