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"A study on the structure of the gonad of Fluta alba was made in the Laboratory. Data concerning the sexuality and body length showed that the smallest female and male recorded were 17.6 and 21.1 cm respectively. It was also found that smallest intersexes were 25 to 29.9 cm. One of the intersexual eels collected had the longest body length, i.e. 64.4 cm. Histological evidence showed that the change of the gonad from female to male were usually found after the lost of ovarian tissues and of proliferation of the interstitial cells in the inner zone of the gonadal lamella. At the same time the formation of the testicular lobules occured by proliferation of spermatogonia. The karyotype of Fluta alba exhibited six pairs (12 chromosomes) and all chromosomes were metacentric. There were no differences in number and morphological structures of chromosomes among sexes, therefore it is suggested that the change of the gonadal function in F. alba is not a genetically inherited, but it might be due to the hormonal regulations produced by the gonad."

"Perhitungan serta pengamatan morfologi kromosom untuk menganalisis konsepjenis telah dilakukan pada Zingiber amaricans Blume, Zingiber aromaticumValeton, dan Zingiber zerumbet (L.) Sm. Sediaan kromosom dibuat denganmenggunakan kombinasi metode Jong (1997) dan metode Darnaedi (1991).Ketiga jenis tersebut memiliki jumlah kromosom sama (2n= 22), tetapimempunyai susunan kariotipe yang berbeda. Perbedaan susunan kariotipetersebut didukung oleh data morfologi, anatomi, polen, dan senyawa kimia daripenelitian terdahulu. Kesimpulan yang dapat dirumuskan, yaitu adanya variasisusunan kariotipe mengindikasikan perbedaan yang dapat digunakan sebagai ciritaksonomi untuk memberi batasan pada setiap jenis. Dengan demikian, hasil studisitotaksonomi mendukung pemisahan Zingiber amaricans Blume, Zingiberaromaticum Valeton, dan Zingiber zerumbet (L.) Sm. sebagai tiga jenis yangberbeda, bukan sebagai species complex. Selain itu, hubungan evolusi dapat puladiperkirakan melalui kariotipe. Jenis Z. zerumbet yang memiliki kariotipe palingsimetris dianggap relatif primitif dibandingkan dengan kedua jenis kerabatnya."