macronucleusn.

1887 Jrnl. Royal Microsc. Soc. 7 973 In the next two stages..the nuclear dualism characteristic of the Ciliata is re-established (the old macronucleus having broken up and been eliminated meanwhile).

1892 J. A. Thomson Outl. Zool. 101 In the ciliated Infusorians there are two nuclear bodies... The smaller or micro-nucleus lies by the side of the larger or macro-nucleus.

1946 Nature 23 Nov. 750/2 It has long been known that the micronucleus of ciliates divides mitotically while the macronucleus is amitotic.

1964 M. Hynes Med. Bacteriol. (ed. 8) xxviii. 436 Stained preparations [of Trypanosoma gambiense] show two nuclear structures; the one, larger and centrally placed, is known as the macronucleus or trophonucleus and the other, smaller, placed at the posterior end, is known as the micronucleus or kinetoplast.

1998 Nucleic Acids Res. 26 4230 During the formation of a new macronucleus in the ciliate Euplotes crassus, micronuclear chromosomes are reproducibly broken at (approximately) 10000 sites.