438 BIOLOGY AND HUMAN LIFE 



oaks. The name cork is a corruption of the Latin quercus, 

 which is the scientific name for all the oaks. We do not make 

 much use of acorns except in some localities as fodder for pigs, 

 but in Italy and other parts of Europe acorns of certain species 

 are a considerable part of the food supply of man. 



4. Mulberry family. The five important plants in this group 

 are the mulberry tree, the leaves of which are the sole food of 

 the silkworm ; the fig plant ; the India-rubber tree of the East- 

 ern Hemisphere ; hops ; and Indian hemp. From a resin in this 

 plant is prepared a dangerous poison hashish, which is some- 

 times used by the natives for its quieting effect upon the 

 nerves ; the after-effects of its use are said to be very bad. 



5. Buckwheat family. In addition to buckwheat and rhubarb 

 this family is chiefly notable for its pernicious weeds— smart- 

 weed, tearthumb, and bindweed being the most common. 



6. Goosefoot family. This is represented in our garden truck by the 

 beet and spinach. Next to the sugar cane (see grass family, p. 436) 

 the sugar beet is the most important source of pure sugar. 



7. Crowfoot order. The American native tulip tree, which furnishes 

 the soft whitewood, and the magnolia, as well as the laurel, sassafras, 

 cinnamon, and camphor trees, belong to this group. 



8. Poppy family. Besides the many attractive flowers for which spe- 

 cies of this group are grown, the drug opium is the most important prod- 

 uct. This drug contains the alkaloid morphin (see page 420). The 

 Chinese government attempted to wipe out the use of opium among the 

 Chinese, and prohibited the production and importation of the drug ; 

 but commercial interests in India and other countries have continuously 

 violated the law 'and made it difficult to save the masses of ignorant 

 people from what is perhaps their worst enemy, 



9. Mustard family. Many common plants come from this 

 group. Besides mustard, from the seeds of which a medicinal 

 product and the seasoning are prepared, we have the turnip, 

 the radish, the horseradish, and the cabbage. There are many 

 varieties of radish as well as of cabbage. Among the latter are 

 Brussels sprouts, kohl-rabi, kale, and cauliflower. From an 

 Oriental form, rape, a fine lubricating oil is produced. 



