Genus and species names are always italicized when printed; the names of other taxa (families, etc.) are not. When a species (or several species of the same genus) is mentioned repeatedly, the genus may be abbreviated after its first mention, as in Q. alba.inomial Nomenclature. The present system of binomial nomenclature identifies each species by a scientific name of two words, Latin in form and usually derived from Greek or Latin roots.
ORDINANCE. A law, a statute, a decree. An ordinance is a law enacted by a municipal body, such as a city council or county commission (sometimes called county council or county board of supervisors). Ordinances govern matters not already covered by state or federal laws such as zoning, safety and building regulations. This word is more usually applied to the laws of a corporation than to the acts of the legislature; as the ordinances of the city of Philadelphia.
Legally, an ordinance is the equivalent of an Act; but is not passed by the legislature. It is a temporary law till its expiry or till it is repealed or till it is approved by the legislature (after which it becomes an Act). Anything that has the power to confer legal rights, obligations, liabilities, etc are laws.