バフンウニにおける二次性徴の発生

概要

論文の詳細を見る
In Hemicentrotus pulcherrimus, the shapes of the genital papilla and the genital pore and the color of the tube feet have been found to show a conspicuous secondary sex dimorphism. The present observation has been carried out to elucidate the problem when and how these secondary sex differences are established. The genital papilla appears first as a flat membrane which covers the genital pore in both sexes (stage 2). Thereafter, in the male the membrane grows until it comes to form a conical epidermal protuberance, whereas in the female it retains its flat membranous or mound-like structure (stage 4). The genital pore shows a round shape at its first appearance in both sexes (stage 2). The elliptical pores (a male character) develop as the diameter of the pore increases (stages 3A and 3B), and at stage 4 the sexual difference becomes statistically significant. The tube feet on the oral side are white in the stage 1 urchin. The sex dimorphism becomes clear when the gonad matures (stages 3B and 4), i. e., white in the male and yellow in the female.
社団法人日本動物学会の論文
1970-02-15