Natural History. S5 



been written since the discovery of the Mendelian principles. 

 Its usefulness is attested not only by its wide adoption as a text- 

 book in English-speaking countries but also by its translation into 

 other languages. 



The present revision will restore the book to its former pres- 

 tige. In it both the student and the general reader may find the 

 essential facts of the rapidly advancing science of heredity pre- 

 sented in a most orderly, intelligible, and discriminating manner. 



w. k, c. 



3. A Naturalist in the Great Lakes Region; by Elliot Row- 

 land Dowxixg. Pp. xxv, 328, with 452 illustrations. Chicago, 

 1922 (The University of Chicago Press). — The object of this 

 book is to place in the hands of school children an intelligible 

 and inspiring story of the natural world about them. The first 

 chapter shows them the unfinished world at their* feet, with the 

 elements ever at work changing the topography of hill and valley 

 — filling up the ponds and eroding the mountains. They next 

 read about the world in the making and the story told by the 

 rocks and by the boulders in the fields as to the changes which 

 have taken place on the surface of the earth in its past history. 

 Then the living world is surveyed and the adjustment among the 

 different groups of organisms is pointed out. This is followed 

 by visits to the dunes, the ponds, the swamps, forest, prairie, 

 ravine, brook, and river. In each of these pleasant and instruc- 

 tive excursions the reader makes the personal acquaintance of the 

 more interesting plant and animal inhabitants of the regions and 

 learns the reasons why each has become settled in its particular 

 environment. Although the modern name for this method of 

 studying nature may be ecology, it is, nevertheless, good old- 

 fashioned natural history. 



The book is most attractively bound in flexible covers and will 

 go easily into a coat pocket, and it should be carried afield not 

 only by the pupil in nature study courses, but also by grown-ups 

 whenever they are fortunate enough to have an hour to spend 

 with nature. w. r. c. 



4. La Constitution des plantes vaseulaires revelee par leur 

 Ontogenie; by Gustave Chauveaud. Pp. xiii, 155, with 54 text- 

 figures. Paris, 1921 (Payot & Cie.). — In this interesting 

 pamphlet the author explains and defends his theory of the 

 ' ' phyllorhiza," ' according to which the f unclameiital unit of the 

 vascular plants is neither the stem nor the leaf but a composite 

 organ composed of a leaf-like part united to a root-like part. In 

 certain aquatic pteridophytes these units are clearly shown by 

 young embryos; the first phyllorhiza gives rise to a second by 

 means of a vegetative point arising laterally, the second gives 

 rise to a third, and so on. At first the successive phyllorhizas 

 remain distinct but. as development goes on, they become more 



