Horse outward similarity is an unreliable measure of relatedness. Besides the horse, there are six other species of genus "Equus" in the Equidae family. These are the ass or donkey, "Equus asinus"; the mountain zebra, "Equus zebra"; plains zebra, "Equus quagga"; Grévy's zebra, "Equus grevyi"; the kiang, "Equus kiang"; and the onager, "Equus hemionus". Horses can crossbreed with other members of their genus. The most common hybrid is the mule, a cross between a "jack" (male donkey) and a mare. A related hybrid, a hinny, is a cross between a stallion and a jenny (female donkey). Other hybrids include the zorse,
Agapanthus africanus at the close of the 17th century. Unlike the more common "A. praecox", it is not generally suitable as a garden plant, and will not tolerate extended freezing temperatures. Agapanthus africanus Agapanthus africanus (African lily) is a flowering plant from the genus "Agapanthus" native to the area of Cape of Good Hope in South Africa. "A. africanus" is more difficult to grow in gardens than "A. praecox", and almost all plants sold as "A. africanus" are actually "A. praecox". It has a short stem bearing a tuft of long, narrow, arching leaves 10–35 cm long and 1–2 cm broad, and