Abstract
The chromosome numbers were investigated in 24 spontaneous populations of 10 clover species in Algeria. The numbers found confirm those already cited by various authors throughout the word, exception made for T.scabrum which had manifested two chromosome numbers, the first, 2n=10, confirmed by numerous authors, the second, 2n=12, newly observed during our present work. The diversity would be linked to the number of pods, the size of fruiting heads and some ecological factors of the environment of origin.