Abstract
Phosphorus‐32 was absorbed by the mycelium of Collybia velutipes and translocated to the pilei of intact sporophores within 1.5 hours. In the stipes upward translocation occurred first in the peripheral hyphac followed by movement of the isotoipe into the central hyphac. After 3.0 hours hyphae in the two regions were about equally labelled with the isotope. Except for very minor differences hyphal was the same in the peripheral and central portions of the stipe.