NA TURE 



0°/ 



THURSDAY, JUNE 12, 1913. 



SEEDS OF FLOWERING PLANTS. 

 Studies in Seeds and Fruits : an Investigation 

 with the Balance. By H. B. Guppy. Pp. xii + 

 528. (London: Williams and Norgate, 1912.) 

 Price 155. net. 



IN this work we find the results of Mr. Guppy 's 

 investigations on the seeds of several flower- 

 ing plants. The investigations seem to have been 

 prompted by a statement by Goebel to the effect 

 that the biology of the ripening fruit has hitherto 

 scarcely received attention, and a further state- 

 ment by Pfeffer that the means by which the power 

 of resistance to drying is gained and the changes 

 which cause its loss are quite unknown. 



Such subjects are investigated as the per- 

 meability and impermeability of seeds, their 

 hygroscopicity, shrinking and swelling, their 

 homologies, their dehiscence, the proportions of 

 the different parts of the fruits, the relation be- 

 tween the number of seeds and the size and weight 

 of the fruit, the abortion of ovules and the failure 

 of seeds, seed coloration, the weight of the 

 embryo, the rest period of seeds, and finally "the 

 cosmic adaptation of the seed." It is impossible 

 in the space of a short review to give any adequate 

 ideas of the whole of the author's investigations. 



From the beginning his " usual plan of follow- 

 ing indications was adopted, forming crude hypo- 

 theses as [he] went along, and dropping them as 

 soon as they had lost their usefulness. Many- 

 points, of course, remained undetermined," and Mr. 

 Guppy only offers " a contribution to the study of 

 a difficult but highly interesting subject." In the 

 cases investigated it was found that all the ovules 

 begin to respond to fertilisation ; but it frequently 

 happened, as in Arenaria, Stellaria, Primula, 

 Scilla, and Iris, that only two-thirds of the original 

 complement of ovules developed into mature 

 seeds. In several legumes a marked constriction 

 results from the abortion of the ovules, the degree 

 of constriction being determined by the number 

 of contiguous failures. 



Special stress is laid on seedless fruits, where 

 the fruit develops under the stimulus of pollina- 

 tion but the seeds fail. The author's results, so 

 far as they go, are full of interest, and he fully 

 realises that much more must be determined before 

 it is possible to draw safe generalisations. To 

 some readers the book will appear discursive and 

 perhaps unconvincing, and without doubt the 

 salient features of the work could have been 

 expressed in fewer words ; but throughout the 

 book one sees the unprejudiced observer at work, 

 and many of the results obtained are both interest- 

 NO. 2276, VOL. 91] 



ing and important. Its very discursiveness has a 

 kind of charm, and there is an occasional incisive- 

 ness which is refreshing, as in the following : — 



" Lord Avebury would regard such persistently 

 functionless ovules as carrying us back to the time 

 when ... all the ovules develoned into seeds. 

 Prof. Bower holds a similar view with reference to 

 the abortive ovules in the beak of a fruit of 

 Anemone nemorosa. . . It should, however, be 

 pointed out that this would not follow if we accept 

 the standpoint taken by Dr. Goebel . . . that 

 functionless organs in plants are not necessarily 

 I he vestiges of former completely developed ones, 

 and that many more primordia are laid down than 

 become functional." 



Each chapter is supplied with a full and useful 

 summary, and there is an excellent index. It is 

 refreshing to find that Mr. Guppy is not content 

 with vaguely referring to authorities, but supplies 

 the name of the work and the volume and the 

 page of the authors he refers to. In this last 

 respect, as well as in some others, his methods 

 are worthy of being adopted by more pretentious 

 writers. 



ENGINEERING SCIENCE.. 

 Mecanique Appliquee. By Prof. John Perry. 

 Ouvrage traduit sur la Neuvieme Edition 

 Anglaise par E. Davaux. Avec des additions et 

 un appendice sur la mecanique des corps defor- 

 mables by E. Cosserat and F. Cosserat. Tome 

 Premier. L'Energie Mecanique. Pp. vii + 398. 

 (Paris : A. Hermann et Fils, 1913.) 



THERE must surely be few text-books about 

 which such conflicting opinions are held as 

 this well-known book on applied mechanics by 

 Prof. John Perry. One of these opinions, favour- 

 able to the book, is held by a majority of teachers 

 of engineering science and by almost all engineers. 

 The other, which is equally unfavourable, is con- 

 fined to a minority of teachers — doubtless the 

 "academic persons " to whom the author so often 

 refers. There must be something fundamental, 

 some conflict of principle, which can produce so 

 wide a difference of opinion between persons 

 equally competent to judge. We are aided in 

 arriving at the nature of this conflict by the fact 

 that engineers outside the colleges are almost 

 universally in its favour; as they are, indeed, of 

 each of the author's text-books relating to engin- 

 eering subjects. Perhaps a parable may be 

 admitted. We picture two travellers desirous of 

 arriving at the same destination, one of them alert 

 to have all the precise formalities of the journey 

 carefully observed, and the other careless of by- 

 laws, and only careful that he shall arrive at his 

 destination by a road which, while reasonably 



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