Occurrence of perforated ray cells in genera of Pachycereeae (Cactaceae)

Abstract

Perforated ray cells are reported for the first time for 16 species of seven genera of Pachycereeae. The perforated ray cells are shorter than vessel elements and have simple perforation plates and small alternate intervascular pits. Among Cactaceae these specialised cells seem to be related with splitting of the tall rays.