Any of several species of butterflies (family Pieridae) that are found worldwide. Adults have a wingspan of 1.5–2.5 in. (35–60 mm). The colour and pattern of many species vary seasonally and between sexes, but they are generally bright yellow or orange. Some have two colour patterns; for example, Colias eurytheme is usually orange with black wing margins, but some females are white with black margins. Pupae are attached to a twig by a posterior spine and a girdle of silk. The larvae feed on clover and may seriously damage crops.
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Any of a diverse group of bacteria that are capable of metabolizing sulfur and its compounds and are important in the sulfur cycle. Members of the genus Thiobacillus, widespread in marine and terrestrial habitats, react with sulfur to produce sulfates useful to plants; in deep ground deposits they generate sulfuric acid, which dissolves metals in mines and corrodes concrete and steel. Desulfovibrio desulficans reduces sulfates in waterlogged soils and sewage to hydrogen sulfide, a gas with the common rotten-egg odour.
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Sulfur crystals from Sicily (greatly enlarged)
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The racial makeup of the city was 93.43% White, 4.41% African American, 0.33% Native American, 0.37% Asian, 0.04% Pacific Islander, 0.35% from other races, and 1.06% from two or more races. Hispanic or Latino of any race were 1.49% of the population.
There were 7,901 households, out of which 34.6% had children under the age of 18 living with them, 53.2% were married couples living together, 13.8% had a female householder with no husband present, and 29.1% were non-families. 24.9% of all households were made up of individuals and 10.1% had someone living alone who was 65 years of age or older. The average household size was 2.56 and the average family size was 3.06.
In the city the population was spread out with 27.1% under the age of 18, 9.5% from 18 to 24, 28.2% from 25 to 44, 21.7% from 45 to 64, and 13.4% who were 65 years of age or older. The median age was 35 years. For every 100 females there were 92.1 males. For every 100 females age 18 and over, there were 88.9 males.
The median income for a household in the city was $38,247, and the median income for a family was $45,455. Males had a median income of $38,235 versus $22,500 for females. The per capita income for the city was $21,615. About 7.5% of families and 9.3% of the population were below the poverty line, including 10.0% of those under age 18 and 11.5% of those age 65 or over.