The evidence for a meiotic process in the euglenineae

Summary Cells of Hyalophacus ocellatus are described which contain either a nuclear figure consisting of a double complement of highly condensed chromosomes arranged in pairs in the anterior half of the cell, or a huge posteriorly-placed nucleus consisting of long granular chromosomes which also show signs of pairing. These nuclear figures are quite unlike interphase nuclei or stages in mitosis and are thought to be stages in euglenoid meiosis.No evidence has been obtained for a sexual fusion of gametes or cells. Previous accounts of sexuality and autogamy in the Euglenineae are historically reviewed and critically discussed relative to the present observations.This paper is dedicated to Professor Dr. E. G. Pringsheim on the occasion of his 80th birthday, with gratitude both for his untiring advice on my research and for his friendship.