BIOLOGY. 335 



Sources of Theine. — The Kola-nut of tropical West Africa, the 

 seeds of which have from time immemorial been highly prized as 

 a tonic by the natives of that region, liave lately been sliown by 

 Mr. Daniell and Dr. Attfield, in two papers read by them before 

 the Pharmaceutical Society, to contain theine. The Kola-tree 

 {Cola acuminata, Robert Brown), also known by the name Ster- 

 culia acuminata, belongs to the natural order SterculiacecB. In 

 Soudan its seeds are called ' ' guru-nuts." It is the fifth source of 

 the alkaloid theine or caffeine with which we are at present ac- 

 quainted. The others are the tea-tree Thea, the coifee-tree Gof- 

 fea Arabica, the Paraguay tree or mate Ilex Paraguay ensis, and 

 guarana Paullinia sorhilis. The seeds of tlie latter are extensively 

 used in Brazil for the preparation of a sort of cocoa. It has ofteii 

 been remarked that theine is contained in the beverages in use 

 among three-fourths of the human race. The discovery of this 

 alkaloid in the kola-nut, which is mentioned by all African travel- 

 lers as being an important article of commerce, still further con- 

 firms the truth of this remark. 



Number of Useful Plants. — "Cosmos" states that, according 

 to a German author, the number of useful plants has risen to 

 about 12,000 ; but it must be remembered that these researches 

 have been completed only in certain parts of the earth. There 

 ai-e no less than 2,500 known economic plants, among which are 

 reckoned 1,100 edible fruits, berries, and seeds; 50 cereals; 40 

 uncultivated edible graminaceous seeds ; 23 of other families ; 260 

 comestible rhizomes, roots and tubers ; 37 onions ; 420 vegetables 

 and salads; 40 palms; 32 varieties of arrowroot ; 31 sugars; 40 

 saleps. Vinous drinks are obtained from 200 plants ; aromatics 

 from 266. There are 50 substitutes for coffee ; 129 for tea. Tan- 

 nin is present in 140 plants ; caoutchouc in 96 ; gutta-percha in 

 7 ; resin and balsamic gums in 389 ; wax in 10 ; grease and 

 essential oils in 330 ; 88 plants contain potash, soda, and iodine ; 

 650 contain dyes ; 47 soap ; 250 fibres which serve for weaving ; 

 44 ai-e used for paper-making ; 48 give materials for roofing ; 100 

 are employed for hurdles and copses. In building, 740 are used ; 

 and there are 615 known poisonous plants. According to Endlicher, 

 out of the 278 known natural families, 18 only seem, up to the 

 j)resent tune, to be perfectly useless. 



