290 



NA TURE 



[Januakv 26, 1905 



likewise be admitted for the beings lowest in the scale. 

 But then, we may add, on the supposition that the 

 scale rests on pure matter, it is not on the lowest grade 

 that we find the infinitely minute creatures, but already 

 some way up, so much so that the gap separating 

 them from the bottom is infinitely greater than that 

 which they would have to traverse to arrive at the 

 summit." 



In conclusion, it may be said that everyone 

 interested in the study of microscopic forms of life will 

 welcome this work from the hand of an enthusiastic 

 observer, who has a most intimate knowledge at first 

 hand with the creatures about which he is writing, 

 and who has achieved a wide reputation as an investi- 

 gator of the fresh-water Protozoa. The work is 

 weakest on the side which deals with the minuter 

 phenomena of the cell and nucleus, especially in re- 

 lation to reproduction, the study of which during the 

 last decade has developed with such rapidity and has 

 brought forth results of such fundamental importance 

 in biology. The author is evidently more of a 

 naturalist than of a cytologist, but it is perhaps too 

 much to e.xpect detailed cytological work in a system- 

 atic monograph even of a group of Protozoa. As a 

 general survey of the peculiar forms dealt with it will 

 be found most useful, not only as an exposition of the 

 present state of knowledge, but even more as in- 

 dicating how much still remains to be worked out 

 with regard to the affinities of the Heliozoa and allied 

 forms of life. By directing attention to the many 

 interesting problems these lowly creatures present for 

 solution, it may be hoped that this monograph will 

 act as a guide and stimulus to investigators in all 

 countries. E. k. M. 



TREES. 

 Trees. By Prof. H. Marshall Ward. Vol. i. Buds 

 and Twigs. Pp. xiv + 27i. Vol. ii. Leaves. 

 Pp. x + 348. (Cambridge : University Press, 1904.) 

 Price 4s. 6d. net each. 



AS one might naturally expect from the scant atten- 

 tion which has hitherto been given to the study 

 of forestry in this country, our literature on the subject 

 is by no means what it ought to be. True, we have 

 several standard works, excellent of their kind, which, 

 however, deal with trees more from a sylvicultural 

 than from a botanical aspect. Students of forestry, 

 and especially students of forest botany, and all those 

 interested in the growth and cultivation of trees, have 

 long felt the great want of a suitable text-book or 

 guide to their studies, but happily now, with the 

 appearance of the above handbook from the facile pen 

 of Prof. Marshall Ward, this want has become a thing 

 of the past. 



The work will consist of several parts — each part 

 forming a volume — the first of which is already to 

 hand, and treats of buds and twigs. The mere men- 

 tion of buds and twigs might suggest to some a dry, 

 uninteresting study of minute details ; but never was 

 a greater mistake made than to imagine such is the 

 case. The study of our trees and shrubs in their 

 winter condition has a fascination all its own, and, in 

 addition to this, the clear and simple way in which 

 NO. 1839, VOL. 71] 



the author treats the subject is sure to inspire many 

 with interest and enthusiasm for the study of forest 

 botany. 



The study of the minute structure of plants in the 

 laboratory has in many cases received the lion's share 

 of attention, with the result that students have been 

 taught to know the internal structure of plants before 

 they were able to recognise these plants in the field. 

 The author clearly recognises this fact, and plainly 

 states that his object is to bring the student more into 

 touch with the plant in its natural surroundings, where 

 he may form a personal acquaintance with it and learn 

 to observe and note facts for himself, and thereby lay 

 a solid foundation for the further study of the biology 

 of the living plant of whatever kind or nature. The 

 opening chapter gives a short but clear account of the 

 general segmentation of the plant. The next eight 

 chapters are devoted lo a consideration of buds. The 

 different kinds, structure, position, arrangement, and 

 function are described in a most masterly and interest- 

 ing fashion. The next seven chapters deal with the 

 different kinds of shoots — their tegumentary systems, 

 leaf-casting and the formation of leaf scars, lenticels, 

 twigs and other accessory characters. 



TTie second portion of the book contains a very com- 

 prehensive classification of trees and shrubs according 

 to characters afforded by their buds and twigs. The 

 classification is accompanied by a complete set of illus- 

 trations, showing very clearly in pictorial form all 

 those features by which the species may be determined 

 in their winter condition. Most of those drawings 

 have been done by Miss Dawson, of the County School, 

 Cambridge, to whose artistic skill they do great credit. 

 The other illustrations with which the volume teems 

 have been obtained from various sources, and are all 

 duly acknowledged by the author. 



The work will be found indispensable to those 

 students who wish to make an expert study of forest 

 botany, .^t the same time it is expressed in language 

 so clear and devoid of technicalities that the amateur 

 who wishes to know something about our trees and 

 shrubs will find this one of the most useful guides to 

 which he can turn. 



Succeeding volumes will deal with leaves, in- 

 florescences and flowers, fruits and seeds, seedlings, 

 and the habit and conformation of the tree as a whole, 

 and each of those volumes, like the present one, will 

 contain diagnostic tables at the end, devised for use 

 in the field. 



From the foregoing it will be seen that the work is 

 a many-sided one, acting not only as a guide to the 

 naturalist in the field, but also as a laboratory hand- 

 book, where the use of the lens and microscope may 

 be employed to amplify the study of objects already 

 observed in their natural habitats. 



Botanists generally, and especially forest botanists, 

 will welcome the appearance of this book as supplying 

 a decided want, and filling a distinct gap in our 

 literature of forest botany. 



Since the above was written the second volume has 

 appeared, .^s already stated, it deals with leaves, and, 

 like vol. i., consists of a general and a special part. 



The general part contains an admirable and ex- 

 h;uistive treatment of the external features of leaves, 



