Junk, 1920] FORESTRY 289 



1985. Willis, .J. C. The sources and distribution of the New Zealand flora, with a reply 

 tocriticism. Ann. Mntimy 32: :r.«>- :>r>7. 7 jitj. lump. July, 1918. [n this article the author 

 employs facts concerning the flora of New Zealand and adjacent islands in defense of bis age 



and area hypothesis. It is emphasized that the hypothesis is meant to apply only in ease 

 about twenty allied species and not in individual cases. The age and area explanation of 

 species distribution is to be regarded as :i general law whoso action may be more or less ob- 

 scured by the presence of active factors other than age. Twenty-eight questions are pro- 

 posed which must be answered satisfactorily by the supporters of the dying-out hypothesis 

 in order to fully substantiate their claims. The age and area hypothesis accounts for the 

 presence and distribution of endemics more convincingly than the assumption that they are 

 representatives of a relict flora. In its present stage of development the theory is entirely 

 incapable of accounting for the relative age of herbs, shrubs and trees. — P. D. Slrausbaugh. 



1986. Willis, J. C. The flora of Stewart Island (New Zealand): a study in taxonomic 

 distribution. Ann. Botany 33: 23-46. 2 fig. 1919. — The author tests his well-known age- 

 and-area hypothesis in a study of the flora of Stewart Island, south of the South Island of 

 New Zealand. Knowing the flora of New Zealand and of three sets of widely separated out- 

 lying islands, and assuming in accordance with the conclusion reached in a previous article 

 that New Zealand has been populated by two great invasions, one northern and one south- 

 ern, the author predicts what the flora of Stewart Island should be if the agc-and-area hypoth- 

 esis is correct. He also makes many predictions of details in connection with the proportion- 

 ate representation of groups of various ranks, affinities of endemics, width of distribution etc. 

 All his predictions proving correct with a wide margin, the author maintains that the age- 

 and-area law on which they were based is by far the principal factor in determining geograph 

 ical distribution. — W. P. Thompson. 



FOREST BOTANY AND FORESTRY 



Raphael Zon, Editor 



19S7. Afzal, Muhammed, and others. Progress report of forest administration in Bal- 

 uchistan for 1917-18. 20 p. Calcutta, 1919. — A routine report on forest operations in the 

 province. — E. R. Hodson. 



1988. Amilon, J. A. Hojdtillvaxtens forlopp hos trad med olika ljusbehov. [The march 

 of height growth in trees of different light requirements.] Skogsvardsforen. Tidskr. 17:95-108. 

 1919.— Statistics in regard to relative light requirements and rate of height growth for differ- 

 ent tree species in Sweden show that the culmination of height growth occurs earlier in the 

 "light-demanding" than in the "shade-enduring" species. The most "light-demanding" spe- 

 cies such as larch, birch and pine, attain their maximum rate of height growth at 10-15 years, 

 while in the most "shade-enduring" species, such as spruce and beech, the maximum is reached 

 at 30-40 years. This relation does not always hold in comparing trees growing on different 

 sites and under different climatic conditions. Such discrepancies, however, are apparent 

 rather than real, due to the fact that under favorable growing conditions the age of a tree as 

 expressed in calendar years is not a true index of its progress in the life cycle of the species. 

 Height growth culminates later, as measured in years, in a tree growing under unfavorable 

 conditions than in a tree of the same species growing under favorable conditions. It is also 

 commonly accepted that trees growing under unfavorable conditions have higher light re- 

 quirements than trees of the same species growing under favorable conditions of soil and 

 climate. The author concludes that if proper standards of comparison are utilized the rela- 

 tive light requirements and the culmination of height growth remain the same for a given 

 species under varying conditions of site and climate. — G. A. Pearson. 



1989. Anonymous. American substitutes for boxwood. Sci. Amer. 120: 223, 236. S fig. 

 1919. — Florida boxwood and wahoo are the only native woods having properties approaching 

 boxwood (Turkish, Persian, Corsican or English). Witch hazel, great rhododendron, moun- 



