Chiasmata in spermiocytes of Locusta migratoria.Eleven bivalents and one X-chromosome (x) are shown in the picture. Chiasmata occur at any spot along the chromosome (interstitial, ic) or at the termini of the bivalents (tc). The bar represents 10 µm. (This is an animal example (a locust), because the chromosomal structures are easier to depict than in plants.)
(B.BERNELOT-MOENS, P.B. MOENS, 1986)