1973 年 38 巻 4 号 p. 645-649
Twenty-nine bivalents were found in the PMCs of Euryale ferox from Gorak-hpur, Eastern India. Primary and secondary association was noted at diakinesis and metaphase respectively. Secondary association at metaphase I both from equatorial and polar views showed the formation of quadrivalents, hexavalents, and octavalents in descending order of frequency. The phenomenon persisted even at metaphase II. Presence of strong secondary association in the species suggests its gametic number to have originated secondarily by means of allopoly-ploidy.