86 NATURAL SCIENCE. February. 



Some American Botany. 



The seventh annual report of the Missouri Botanical Garden 

 which has just reached us contains, besides information about the 

 gardens, several scientific papers. In fact, the garden-report ends at 

 page 24 ; the rest of the book (which contains 209 pages) being 

 occupied with papers dealing with the botany of the United 

 States, a short address on the value of a study of botany, and a cata- 

 logue of a collection of books on pre-Linnean botany, the generous 

 gift of Dr. Lewis Sturtevant. The plates are, as usual in these 

 reports, excellent. There are no less than sixty-six to illustrate the 

 three scientific papers, and also half-a-dozen depicting various plants 

 of interest which have flowered during the year. Among these we 

 note the Victoria regia. As the flowers of this great water-lily expand 

 in the twilight the garden was on several occasions kept open in the 

 evening to enable those who wished, to witness this interesting 

 function. Professor Trelease, the director, contributes an account of 

 the Juglandacea of the United States, in which special attention is 

 drawn to such characters of the fruit, twig, bark, and bud as will be 

 helpful in field studies. So well-marked are some of these characters 

 that in the case of the hickory " most of the species are more readily 

 known in their winter condition than during the period of flowering." 

 The same is true of the walnuts. Some excellent photographs of 

 portions of the trunks of different species give a good idea of the 

 appearance of the bark, which shows marked differences according to 

 the species. Miss Mulford contributes a descriptive revision of the 

 agaves of the United States. Most of the agaves have their home in 

 arid deserts of Mexico, Central America, and the south-western 

 portions of the States. Owing to the rarity with which they bloom 

 under cultivation they have earned the popular name of " Century 

 plant." In their own country they have been used by man from time 

 immemorial. The Aztecs showed their appreciation by reverencing 

 the plant as a god. Saddle-cloths, sacks, and ropes have been made 

 from the tough fibres, and Miss Mulford quotes, on Humboldt's 

 authority, "a bridge at Quito, having a span of 130 feet, made of 

 ropes of agave fibre four inches in diameter." The softer parts supply 

 food and drink. Pulque, a universal drink in Mexico, is made by 

 allowing the sweet sap of the best-known species. Agave amcricana, to 

 ferment in vats of raw hide. This species blooms at ten years of age. 

 When it is about to send up its large flowering-stalk an enormous flow 

 of sap takes place towards the central bud to meet the necessary 

 expenditure. The Mexicans and Indians cut out the bud and sur- 

 rounding leaves and collect the liquor, which flows freely from the 

 wound, in a long cylindrical gourd. "Some plants produce an average 

 of two gallons a day, and will keep up the supply for months." The 

 leaf-spine with attached fibre serves as a ready-threaded needle ; 

 the strong flowering-stalks make handles for lances, poles for fishing, 

 walls for houses ; and it is said that the juice mixed with wall-plaster 



