Males of two closely related, co-occurring species of Lycaena butterflies have dorsally blue (Lycaena heteronea) or red-orange plus ultraviolet (Lycaena rubidus) wings. Males are selectively territorial against conspecific males. Virgin females accept only conspecific males, probably chosen by wing color. Females are nonterritorial and spend most of their adult activity ovipositing on the corre...

ICROSCOPIC observation, as well as solubility tests and studies of the M effects of gene substitutions, have shown that the normal, wild type eye color of Drosophila melafiogaster is due to the presence of two pigments, red and brown. These two pigments are the end products of two largely independent chains of reactions. Recent work on the genetic control of eye color in Drosophila was almost e...

The nucleotide sequence of the red-sensitive visual pigment gene, R007Af, in the fish Astyanax fasciatus, from the initiation codon to the stop codon of this gene, including introns, is 1,592 bp, making it the shortest visual pigment gene known in vertebrates. Analysis of this and other homologous sequence data suggests that vertebrates initially had two duplicate genes and that each ancestor o...

Iron is eliminated in the bile of normal dogs at a low but quite constant rate, 0.2 mg. per day. The feeding of large amounts of iron to normal dogs does not cause an increased iron excretion in the bile nor does the injection of considerable quantities of colloidal iron by vein. When red cell destruction is brought about by acetyl-phenylhydrazine the elimination of biliary iron may increase te...