578 



NATURE 



[April i8, 1895 



the curvature of the growing region which may have been 

 induced by a previous stimulation. Attention is here 

 called to the brilliant experiments of Prof. Pfefler, which 

 have demDnstrated conclusively that the tip of the root 

 is alone sensitive to gravitation, thus finally confirming 

 the conclusion drawn by Darwin from less decisive ex- 

 periments. The announcement of this discovery by Prof. 

 Pfeffer was one of the most interesting incidents in the 

 Biological Section at the Oxford meeting of the British 

 Association. 



A self-recording method for studying the sleep-move - 

 ments of leaves, strikes us as especially valuable. 



The second part of the boo'c, on the chemistry of 

 metabolism, is of quite a diflferent character from part i., 

 and is evidently intended for students with an advanced 

 chemical knowledge, who alone can make intelligent use 

 of it. The object aimed at is sufti:iently explained in 

 the opening paragraph : 



"The practical study of the transformations which 

 plastic substances undergo in metabolism, is an applica- 

 tion of organic chemistry ; the immediate problem is 

 generally to determine whether certain substances are 

 present or absent, and, if present, in what am junts in 

 particular tissues." 



The mode of determination of all the important 

 organic bodies occurring in plants, such as protein, 

 amides, oils, carbohydrates, tannins, acids, and enzymes, 

 is concisely explained. 



There are two appendices, the first of which gives 

 examples of quantitative results obtained in actual ex- 

 periments, in order to show the degree of accuracy which 

 may fairly be expected ; the second is a list of reagents. 



Within the short space of ninety small pages, which is 

 all that the second part occupies, it is obviously impos- 

 sible to give full instruction in such a difficult and com- 

 plicated subject as the practical physiological chemistry 

 of plants. Those, however, who are already good 

 chemists, will no doubt derive great help from the terse 

 directions given here, especially as these are supple- 

 mented by abundant references to the more special 

 literature. 



The authors are much to be congratulated on their 

 work, which fills a serious gap in the botanical literature 

 of this country. We think it very desirable that a smaller 

 edition of the book should be published for use in 

 schools, bearing somewhat the same relation to the pre- 

 sent handbook as Prof. Bower's " Practical Botany for 

 Beginners" bears to his larger manual on the same 

 subject. It is most important, now that physiological 

 botany is supposed to be taught in so many schools 

 throughout the country, that it should really be taught 

 in the only efficient way, namely by experiment, and that 

 it should no longer be made a mere matter of " cram- 

 ming," as is now too often the case. A selection from 

 the present book of the simplest and most fundamental 

 experiments, such as could be performed with tolerable 

 certainty of result in ordmary science-schools, would, we 

 are sure, be of the greatest service to conscientious 

 teachers, who desire to make their scientific instruction 



J.>v 



D. H. S. 



NO. 1329, VOL. 51] 



MUSSEL CULTURE. 



Mussel Culture and the Bait Supply, with reference 

 more especially to Scotland. By W. L. Calderwood. 

 (London : Macmillan and Co., 1S95.) 



THIS little book has been written for the useful pur- 

 pose of calling public attention to the urgent need 

 of an increased supply of mussel bait in the interests of 

 the line fishermen, and in order that the food supply of 

 the country may be increased. It does not contain new 

 facts, but it summarises many old ones, and puts the 

 results of some biological inquiries in a form in which 

 they will be readily available for consultation by 

 members of County Councils and others who ought 

 to be interested in fish-culture. The general conclusion 

 arrived at is one which has been recently pointed out in 

 the pages of Nature, viz. that a systematic cultivation 

 of our foreshores, such as is now carried on in several 

 European countries — ^notably France and Holland — 

 must soon be resorted to if we wish to stop the rapid 

 depletion of our shellfish beds. 



Sixty years ago the supply of mussels for bait must 

 have seemed almost inexhaustible, but now that larger 

 boats with more men and much longer lines are employed, 

 the supply of bait is rapidly failing at many places round 

 the coast, with the result that we have to import at con- 

 siderable expense large quantities of mussels annually 

 from Holland. The fact that it is necessary thus to impor t 

 a mollusc which grows naturally in great abundance 

 on our own shores, is in itself significant of the mis- 

 management—or total absence of management — of our 

 bait beds in the past. Mr. Calderwood gives an account 

 of the various mussel scalps or beds round the Scottish 

 coast, describes their former extent and their presen t 

 condition — in most cases a sad story of wicked waste 

 resulting in woful want — and says : " We have seen our 

 public oyster fisheries slowly decline, and all but expire ; 

 we now are watching our mussel beds as they diminish 

 in the same way." 



It is a pleasant relief to notice that some few 

 beds really arc regulated and well managed, with 

 the result that they are in a flourishing condition. 

 For example, those at Montrose, where "the grounds 

 now under cultivation were at one time all but destitute 

 of mussels, but by the exertions of the Ferryden and 

 Usan Society of Fishermen, led by Mr. James Johnston, 

 'seed' was collected and bedded, and the system of 

 cultivation adopted which has since yielded such excel- 

 lent results" (p. 24). The interesting account of the 

 enterprise of the fishermen at Nairn, in experimenting 

 with mussel culture on their own account, shows how 

 readily new beds may be formed and important results 

 obtained. If such work is to be done, however, to any , 

 great extent, we must adopt the French system of rent- 

 ing, on easy terms, the sea-bottom and foreshore to such 

 individuals as will cultivate the beds, and so render 

 them of increased value to the country. 



We are reminded by Mr. Calderwood, as a proof 

 of the enhanced value of bait, that the sands of 

 Dun, in Scotland, which were not considered by 

 the fishermen to be worth £s a year at the beginning 

 of the century, are now let for ^S^° PC annum. Of 



