BOTANICAL GARDENS 955 



grounds or when received, is given a card of data, like a library accession 

 card, filed in boxes with tab-cards of the genera. The annuals, perennials 

 and greenhouse plants have separate boxes. For each also there has been 

 made a checking list, like the Kew hand list, of all these plants in cultiva- 

 tion in America and those possible to introduce from other countries, the 

 species being checked on these lists when the accession card is filled out. 

 Thus at any time the presence of the plant in the collection can be verified, 

 its history here reviewed, and its location indoors or in the beds discovered. 

 For the convenience of the public a painted metal label is to be placed with 

 each plant indoors and a green painted wooden label in the beds for each 

 species outdoors. All these labels are costly and easily destroyed or mis- 

 placed; in case of doubt the gardener should be asked to refer to the office 

 records, which already are complete to date, while the labels will never be 

 quite completed. 



The Harvard Botanic Garden was established in 1807 and has been 

 in continuous existence since the date of its establishment. It covers an 

 area of approximately seven acres. 'The methods of caring for the plant 

 collection will follow largely those of the Arnold Arboretum, and the plants 

 thus will supplement that great collection, giving this university a com- 

 plete laboratory of plants grown in northern gardens, for use in botany, 

 landscape architecture, horticulture and related studies. The present col- 

 lection (1924) of some two thousand species will be increased rapidly to at 

 least six thousand, while one thousand annuals will be grown. Of the 

 possible ten thousand species of greenhouse plants there is room for per- 

 haps one-third. It is planned to have all the materials of our American 

 nursery catalogues, exclusive of hardy woody plants, in cultivation by a 

 year hence, with as many of the rare plants as can be obtained.' " (Stephen 

 F. Hamblin, Director of the Harvard Botanic Garden, Landscape Archi- 

 tecture, April 1924.) 



Natural Features. 



'The Arnold Arboretum occupies two hundred and forty acres of 

 meadow, hill and valley. The ground rises gradually from the meadow at 

 its northeastern end to the summit of Bussey Hill. From the top of Bussey 

 Hill the ground drops abruptly to South Street on the south and on the 

 southwest to the valley which crosses the arboretum from Centre Street 

 to South Street and which, at the northern base of the second of the hills 

 of the arboretum, Hemlock Hill, is joined nearly at a right angle by the 

 valley through which the Bussey Brook flows from the northwest. Through 

 the low land west of Hemlock Hill and separating it from the third and 

 the highest of the arboretum hills, Peter's Hill, Bussey Street, a highway 

 open to traffic, extends from Walter Street near its junction with Centre 

 Street to South Street. 



The collections of trees in the arboretum are arranged by groups of 

 species which are called genera, and the genera, so far as it has been found 

 practicable to do so, have been planted according to their botanical rela- 

 tionships into larger groups called families. In the case of important North 

 American trees, that they may show their habit under different conditions, 



