Rice is an annual plant with several jointed culms or stems from 2 to 10 feet long, the lower part floating in water or prostrate, with roots at the nodes, the rest erect. The panicle is terminal and diffuse, bowing when the seed is weighty. It is probably indigenous to China, and certainly to India, where the wild form grows by tanks, ditches and rivers. It was early introduced into East Africa and Syria, and later into America, where it already appears as a native plant. In Europe, rice was brought into the Mediterranean basin from Syria by the Arabs in the Middle Ages, but is now grown largely only in the plain of Lombardy, and a little in Spain. In England it has been cultivated merely as a curiosity, and may be seen in the hothouses of most botanic gardens, treated as a water plant. The Cingalese distinguish 160 kinds, while 50 or 60 are cultivated in India, not including the wild form, from which the grain is collected, though it is never cultivated. Most kinds require irrigation, but some need little water, or can be grown on ordinary, dry ground. Oryza (the classical name of the grain), or the husked seeds, is called Bras by the Malays, and Paddy when it is enclosed in the husk. Carolina and Patna rice are the most esteemed in England and the United States. The grain of the first is round and flat, and boils soft for puddings; the latter has a long and narrow grain that keeps its shape well for curries, etc. The flour procured from the seeds is called Oryzae Farina, or rice flour, commonly known as ground rice. The granules of rice starch are the smallest of all known starch granules.