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　　文章：香蕉的历史、纸币发展、味觉和嗅觉、地图发展史

　　香蕉的历史

　　Banana is the common name used for herbaceous plants in the genus Musa， which because of their size and structure， are often mistaken for trees. Bananas are cultivated for their fruit， which bears the same name， and to a lesser extent as ornamental plants. Bananas are of the family Musaceae. Globally， bananas rank fourth after rice， wheat and maize in human food production； they are grown in 130 countries worldwide， more than any other fruit crop. Bananas are native to tropical southeastern Asia but are widely cultivated in tropical regions. In popular culture and commerce， "banana" usually refers to the soft， sweet "dessert" bananas that are usually eaten raw. The bananas from a group of cultivars with firmer， starchier fruit， generally used in cooking rather than eaten raw， are typically known as plantains.

　　The main or upright growth is called a pseudostem， which， when mature， will obtain a height of 2–8 m （varies between different cultivars）， with leaves of up to 3.5 m in length. Each pseudostem produces a single bunch of bananas， before dying and being replaced by a new pseudostem. The base of the plant is a rhizome （known as a corm）。 Corms are perennial， with a productive lifespan of 15 years or more.

　　The term banana is applied to both the plant and its elongated fruit （technically a false berry） which grow in hanging clusters， with up to 20 fruit to a tier （called a hand）， and 5-20 tiers to a bunch. The total of the hanging clusters is known as a bunch， or commercially as a "banana stem"， and can weigh from 30–50 kg. The fruit averages 125g， of which approximately 75% is water and 25% dry matter content. Bananas are a valuable source of Vitamin A， Vitamin C， and potassium.

　　Although the wild species have fruits with numerous large， hard seeds， virtually all culinary bananas have seedless fruits. Bananas are classified either as dessert bananas （meaning they are yellow and fully ripe when eaten） or as green cooking bananas. Almost all export bananas are of the dessert types； however， only about 10-15% of all production is for export， with the U.S. and EU being the dominant buyers.

　　History of banana

　　Banana bunch

　　The domestication of bananas took place in southeastern Asia. Many species of wild bananas still occur in New Guinea， Malaysia， Indonesia and the Philippines. Recent archaeological and palaeoenvironmental evidence at Kuk Swamp in the Western Highlands Province of Papua New Guinea suggests that banana cultivation there goes back to at least 5000 BC， and possibly to 8000 BC. This would make the New Guinean highlands the place where bananas were first domesticated. It is likely that other species of wild bananas were later also domesticated elsewhere in southeastern Asia.

　　The banana is mentioned for the first time in written history in Buddhist texts in 600 BC. Alexander the Great discovered the taste of the banana in the valleys of India in 327 BC. The existence of an organized banana plantation could be found in China in 200 AD. In 650 AD， Islamic conquerors brought the banana to Palestine. Arab merchants eventually spread bananas over much of Africa. The word banana is of West African origin， and passed into English via Spanish or Portuguese.

　　In 15th and 16th century， Portuguese colonists started banana plantations in the Atlantic Islands， Brazil， and western Africa. As late as the Victorian Era， bananas were not widely known in Europe， although they were available via merchant trade. Jules Verne references bananas with detailed descriptions so as not to confuse readers in his book Around the World in Eighty Days （1872）。

　　纸币发展

　　History

　　Paper money originated in two forms： drafts， which are receipts for value held on account， and "bills"， which were issued with a promise to convert at a later date.

　　Money is based on the coming to pre-eminence of some commodity as payment. The oldest monetary basis was for agricultural capital： cattle and grain. In Ancient Mesopotamia， drafts were issued against stored grain as a unit of account. A "drachma" was a weight of grain. Japan's feudal system was based on rice per year – koku. At the same time， legal codes enforced the payment for injury in a standardized form， usually in precious metals. The development of money then comes from the role of agricultural capital and precious metals having a privileged place in the economy.

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