NUCLEAR-DNA CONTENT IN GASTROTRICHA

A cytofluorometric evaluation of nuclear DNA content was carried out o n fifteen species of Gastrotricha. Genome size, ranging from 0.05 to 0 .63 pg, appears uniform in this group and rather low compared to value s found in other lower Metazoa. Differences in DNA content between the two orders of the phylum, Macrodasyida and Chaetonotida, which differ greatly in morphology and reproductive biology, are not evident. From these data, a polyploid condition of obligatory parthenogenetic Chaet onotida seems unlikely.