Chromosome studies in Pisces, II
On the chromosomes of Sillago sihama (Sillaginidae) and Parasilurus asotus (Siluridae)
1951 Volume 26 Issue 3-4 Pages 153-155
Details
1951 Volume 26 Issue 3-4 Pages 153-155
The chromosomes of two teleost fishes, Sillago sihama Forskål (Sillaginidae) and Parasilurus asotus Linné (Siluridae), were investigated in male germ cells during the course of spermatogenesis. The results are summarized as follows:
1. The number of chromosomes in Sillago sihama was decided as 48 in diploid in spermatogonia and 24 in haploid in both primary and secondary spermatocytes (Figs. 1-7).
2. The spermatogonium of Parasilurus asotus shows 58 chromosomes at metaphase. The haploid numer is found to be 29 in the first and second divisions (Figs. 8-14).
3. In these two species, the diploid complement is composed of telomitic rodshaped chromosomes slightly varying in their length.
4. In the two cases described above, no particular chromosomes could be detected throughout the course of the meiotic divisions either in shape or behaviour.
