﻿44'' 



BOTANICAL GAZETTE 



determinations are plotted graphi- 

 regarding the conditions for plant 

 life in such a habitat. The variations in soil moisture, although considerable, 

 do not indicate that this is the factor of most importance in promoting the 

 greater mesophytism of the ravine habitat as compared with the upland. 



shown by a few examples. The average daily rates of evaporation from the 

 standard atmometer for the open upland, the forested upland, the south- 

 facing slope, the north-facing slope, and the bottom of the ravine were respec- 

 tively 16.3, 8.7, 7.9, 6, and 4.7 cc. This shows very definitely that the more 

 or less confined atmosphere of the lower parts of rather narrow ravines has 

 frequently only about one-half the evaporating power possessed by more 

 freely circulating air of the forested upland. Maps of the region north of 

 Chicago in which the ravine is located and of the ravine itself, together with the 

 tabulation and plotting of data and photographs of the vegetation at the 

 various stations, add to the value of the paper.— Geo. D. Fuller. 



New Zealand vegetation. — A non-technical but truly scientific description 

 of the vegetation of any land is interesting and useful, even to botanists, in 

 forming a general concept of the plant growth of that region. In such an article 

 Cockayne 20 has sketched the flora of New Zealand, and has managed to include 

 many facts within the limits of a few pages. Analyzing the composition and 

 affinities of the flora, he finds 74 per cent endemic, while Malayan, Australian, 

 and subantarctic elements follow in decreasing importance, and the final touch 

 is given by a remarkable element composed of species either closely related to 

 or identical with those of the northern hemisphere. 



Among the various plant communities characterized are the rain forest, 

 the southern beech forest, the tussock steppe, the swamp, and the subalpine 

 fell-field. The first of these originally covered all the lowland and montane 

 regions of North Island, and considerable portions of the west and south of 

 South Island. This rain forest was remarkable for the abundance of conifers 

 in such genera as Dacrydium, Podocarpus, and Agathis, mingled with broad- 



the tussock steppe, dominated by large grasses of the tussock habit of growth. 

 The principal species were Danthonia Raoulii, Poa caespitosa, and Festuca 

 novae-zealandiae. Somewhat less attention is devoted to the beech forest with 

 five species of Nothofagus, the heath thickets, swamps, sand dunes, and moun- 



species.— Geo. D. Fuller. 



20 Cockayne, L., The primitive vegetation of New Zealand. Jour. Agric. (New 



