[Conjugation of polytene chromosomes in intraspecies hybrids of the virilis group of Drosophila. II. Hybridization of complementary RNA with polytene chromosomes in specimens].

A cytological hybridization of H-3-complementary RNA synthetized from DNA a template of D. virilis with the polytene chromosomes of D. virilis and the hybrids between D. virilis and D. texana, was carried out in situ. The uridine label of RNA was shown to be located mainly over the disc of the polytene chromosomes, the silver grains in interspecies hybrids being located over both homogous chromosomes including the unpaired gions.