STRUCTURE OF SALIVARY CHROMOSOMES IN BILOBELLA MASSOUDI CASSAGNAU (COLLEMBOLA - NEANURIDAE)

This work is a study of the giant salivary chromosomes of a Collembolan species of the family Neanuridae, Bilobella massoudi, recently discovered in North Jugoslavia. The salivary glands of this species have a great number of nuclei (from 100 to 140) containing polytene chromosomes which are very short and easy to spread. Their number is diploid (2 n=14), with sometimes partial pairing of the homologues and they are characterized by the presence of broad heterochromatic zones. Chromosomes VI and VII produce ringlike nucleoli. Differences of structure are observed in these chromosomes according to ecological conditions which influence the animal's life. © 1968 Springer-Verlag.