Periodical Literature 249 



BOTANY AND ZOOLOGY 



The need of an exact method of analyz- 

 Floristic ing vegetative soil cover, especially in con- 



Analysis nection with gauging the effects on the soil 



Method flora of thinnings, more or less severe and 



from time to time, is discussed at length by 

 Lagerberg. The relation of soil to plant cover and of plant 

 cover to light is briefly explained, and reference is made to Ca- 

 jander's four principal forest types based on soil flora, namely the 

 Oxalis-Majanthemiim type, the Myrtillus type, the Vaccinium 

 type, and the Calluna type (see F. Q., X, p. 520). The propriety 

 of this classification is questioned and declared unsafe. Cieslar's 

 and Knuchel's work on relating soil flora and light are also re- 

 ferred to (see F. Q., XIII, p. 90, and IX, pp. 180 ff.). 



The author then describes two methods of analysis of plant 

 formations. The first by Hult, designed in 1881, was generally 

 employed by plant geographers of northern countries. Hult 

 recognized 10 primar}' biological types: conifers, broadleaf trees, 

 shrubs, dwarf shrubs, grasses, herbs, climbers, foliage mosses, 

 white mosses, and lichens. He recognized five frequency grades . 

 sporadic, sparse, dispersed, plentiful, and dense or frequent. The 

 plants occurring in the latter grade determine the physiognomy 

 of the plant formation. To enable ready characterization, three 

 layers of plant cover were recognized with somewhat definite 

 dimensions: the soil-layer reaching up to 3 cm; the field-layer up 

 to 8 dm in three floors, the lower, middle and highest, limited by 

 1, 3, 8 dm; the shrub-layer up to 2 m, the coppice-layer up to 6 m, 

 and the high forest above. A graphic method was used to show 

 the plant formations according to frequency degrees and layers. 



The author charges against the method lack of objectivity, 

 which makes it useless in determining changes of flora as a 

 result of thinnings, since here investigations must be made with 

 precision and are usually carried on by different persons. 



He then describes a method by Rankiaer, published in 1909, 

 and suitable for this purpose.^ The main point is to rule out all 



1 The reference of this method to the authorship of Rankiaer in 1909 over- 

 looks the fact that Pound and Clements used the method in 1898, and a full 

 description is found in "Research Methods in Ecology," by F. E. Clements, 

 1905. 



