The sections of the light spectrum which the âredâ and âgreenâ cones perceive overlap and this is why red and green colour vision deficiencies are often known as red/green colour blindness and why people with red and green deficiencies see the world in a similar way.
Boston Fern The most common indoor fern, Boston ferns are long-lived plants that can reach more than 5 feet tall and wide at maturity (though indoors they rarely reach that size). Fern breeders have released a large number of varieties -- from selections with golden fronds to fantastically frilled fronds.
Five varieties of the species are widely recognized: 1  Allium canadense var. canadense - most pedicels replaced by bulbils rarely producing fruits or seeds, most of the range of the species. 2  Allium canadense var. ecristatum Ownbey tepals deep pink and rather thick, coastal plain of Texas. 3  Allium canadense var.