Abstract
The male germ-line chromosomes of the Japanese newt, Cynops pyrrhogaster, are revised in its 9 geographical populations by the use of the improved cytological techniques, and their karyotypes are found to be quite uniform and stable. The spermatogonial chromosomes (2n, 24) are all bi-armed and their morphometric characteristics are shown, by way of example, for the Hirosaki-population (Table I). A pair of no. 11 chromosomes somewhat differ each other in shape. No secondary constrictions and satellites are distinguished. Twelve bivalents are observed in Meiosis-I and the same number of dyads in Meiosis-II. Additional observations of mitotic chromosomes of larvae (Hirosaki) reveal that their somatic cell karyotype is similar to the spermatogonial karyotype.
