Chromosome studies in Pisces

Abstract

So far as the author is aware, the chromosomes of gobiid fishes have never been studied by any author. The present paper deals with the chromosomes in male germ cells of Tridentiger obscurus and Acanthogobius flavimanus belonging to the Family Gobiidae. No numerical and morphological differences of chromosomes were observed between these two species, as clearly seen by reference to the accompanying figures (Figs. 1-16). The diploid number of chromosomes counted in the spermatogonial division is 44, all being of telomitic type with gradual difference of length. The only visible difference lies between the smallest two pairs which are quite conspicuous on account of their remarkable minute size in Tridentiger obscurus.The haploid number, 22, is clearly demonstrated in the primary and secondary spermatocytes.In none of the cases described above, there was any evidence for the presence of the particular chromosomes, either in behaviour or in structure.Apparently the chromosome complex of the Gobiidae resembles those in some Pisces such as certain Cyprinidae, Cyprinodontidae, Gasterosteidae, Pholidae and Cobitidae, in many points, i.e. in their number, form and mode of arrangement.