The list is of "taxa", the terms used in the latin names of living organisms.
Kingdom, Phylum, Class, Order, Family, Genus, species.
When referring to an organism by its species in scientific notation, the genus is capitalized and the species is in lower case (eg. Homo sapiens, Felis domesticus). These names are normally italicized or underlined.
Today's brain teaser courtesy of Braingle.com.