512 



NATURE 



[January 9, igi; 



[prescribed for study. The fruits figured include 

 those of sweet pea, wallflower, pansy, and dande- 

 lion. There are curious errors. The "pine " cone 

 fig-ured on p. 11 is the cone of the common spruce. 

 On p. 26, the casting- of tvvig-s, a peculiar process 

 best seen in poplars (which are not mentioned in 

 the vague account), is confused with the natural 

 pruning of the branches of trees due to shade. 

 The flowers of Eucalyptus and Cactus will not be 

 available in many schools ; and teachers are 

 directed to purchase these in a shop somewhere in 

 Yorkshire. There is no lack of material for the 

 study of trees, even in large towns; and the 

 lessons would be most valuable if all the material 

 to be studied were gathered by the children them- 

 selves. 



(3) "Forestry in New England" is an interest- 

 ing book intended for the general reader. The 

 first part is an account in simple language of the 

 general principles of silviculture, with short 

 chapters on cognate subjects, like forest fires, 

 insect and fungoid pests, timber valuation and 

 measurement, &c. The second part is more novel 

 and valuable, being a description of the forests 

 of New England at the present day. There are 

 excellent chapters on their area, composition, 

 modes of management, and financial returns. To 

 the student of ecology, the account of the four 

 forest regions, with their subordinate, types, will 

 be of great interest. The most important region, 

 which includes the most elevated parts of the 

 country, is dominated by the red spruce. The 

 author mentions a remarkable fact, that wherever 

 planting is resorted to, the European spruce 

 (Picea excelsa) is a much superior tree to the 

 native species (Picea rubra), as it grows much 

 faster and yields better pulp-wood. The book 

 contains much information that is new, and of 

 great interest to both the botanist and the forester. 



(4) Prof. Record's treatise is a most valuable 

 contribution to our knowledge of the numerous 

 kinds of wood which are of economic importance 

 in the United States. The different species are 

 admirably distinguished in the concluding part of 

 the book. The first part presents, perhaps, in a 

 clearer light than anything hitherto published in 

 English the salient points in the study of the 

 structural and physical properties of wood in 

 general, each section being supplied with a well- 

 chosen bibliography, which will be of great service 

 to students. This book should be in the hands 

 of foresters, architects, engineers and others who 

 have to deal with the identification and uses of 

 timber. 



(5) In U.S. Forestry Bulletin No. iii, Mr. 

 Plummer sums up an investigation that has been 

 made in the United States on the linbility of trees 



NO. 2254, VOL. 90] 



to be struck by lightning. Observations were 

 taken during the past five years by nearly 3000 

 forest officers over a territory about 200,000,000 

 acres in area. Lightning is one of the chief causes 

 of forest fires in America, being second only to 

 sparks of locomotives as a source of conflagration. 

 Lightning either ignites the tree itself, or probably 

 more often sets fire to the humus at its base. 



Mr. Plummer 's conclusions are opposed to the 

 current belief that some species of trees are more 

 liable to lightning-stroke than others. According 

 to Fischer's theory, oak and poplar, the wood 

 of which contains much starch, are good conductors 

 and attract lightning ; while birch and beech, 

 which have wood containing much oil, are bad 

 conductors and escape. Mr. Plummer denies this, 

 being of the opinion that " the greatest number 

 of trees struck in any locality will be of the domin- 

 ant species." He agrees, however, with previous 

 writers that trees taller than others, those in an 

 isolated position, and those with deep roots, are 

 most in danger from lightning. Trees in general 

 are most liable to be struck when their conductivity 

 is increased, as is the case when their stems are 

 wet with rain. 



European statistics show that the species most 

 often damaged by lightning on the Continent is 

 the black Italian poplar [Populus serotina). The 

 explanation is simple. This tree is extensively 

 planted, always in more or less isolated positions, 

 as along roads or in pastures, or on the sides of 

 streams ; moreover, it grows to a much greater 

 height than the other species that are planted in 

 similar situations. Mr. Plummer is in error in 

 supposing this poplar, which is of hybrid origin, 

 tO' be identical with the American Populus moiii- 

 lifera, which is usually a moderate-sized tree with 

 a rounded crown, seldom struck by lightning in 

 its native countrv. 



OUR BOOKSHELF. 



Primeval Man: The Stone Age in Western Europe. 



By A. Hingston Ouiggin. With an introduction 



by Dr. A. C. Haddon, F.R.S. Pp. 140. 



(London: Macdonald and Evans, 1912.) Price 



15. 6d. net. 

 Mrs. Quiggin has succeeded remarkaljly well in 

 a praiseworthy attempt at striking the mean of 

 anthropological opinion on primeval man, for the 

 benefit of "the hard-working primary teacher or 

 for upper forms." The value of that opinion on 

 many points may be reasonably questioned, and 

 ihe task of compiling a didactic work on the sub- 

 ject must have been a very difficult one. The 

 author, however, cannot be held responsible for 

 canvassed opinions. But who, in such a case, is 

 responsible for the omission from such a book of 

 most material evidence, as definitelv scientific as 



