33^ 



NA rURE 



[August 8, 1895 



ing with the Nymphalids, sub-family Salyruur. In the 

 butterflies, Dr. Scudder has been chiefly followed. 



The family Papilionidir supplies us with an illustration 

 that the book is only written primarily for .-Vmerican 

 students ; for the Piipilioiiincc are distinguished by the 

 black ground-colour, the tail, and the fi\e-branched radius 

 of the fore-wings ; and the Pariuissiimc by the white tail- 

 less wings and four-branched radius, characters not 

 universally exact, though amply sufficient to distinguish 

 the North .\merican forms. 



.\ curious fact is noticed by Prof. Comstock with re- 

 ference to the Garden Whiles. He tells us that the 

 native .American species — Pieris olcracca and Poii/ia pro- 

 toiiitc — have both become greatly lessened in numbers 

 by the increase of the imported European Pieris rapcF. 



.\nother curious fact noticed by Prof. Comstock is that 

 the dog-flea is the common flea of the United .States, the 

 true Pulex irritans being comparatively rare : while the 

 importance of counter-checks in agricultural entomology 

 is illustrated by the author's remark: ''Nothing more 

 wonderful has been accomplished in economic entomology 

 than the subduing in California of the cottony-cushion 

 scale by the introduction from .Australia of a lady-bug, 

 Veiialia, which feeds upon it." 



We cordially commend Prof Comstock's book to 

 European, and especially to British, entomologists : for, 

 although it is written mainly for .American students, it 

 contains much which entomologists of other nations will 

 find both useful and instructive. W. V. K. 



AGRICULTURE AND HORTICULTURE. 

 Agriculture, Praclical and Scientific. By James Muir, 



M.R..A.C. Pp.350. (London: Macmillan, 1895.) 

 Agriculture. By R. Hedger Wallace. (London and 



Edinburgh : W. and K. Chambers, 1895.) 

 Tlie HorticulturisCs Rule-lionk. By L. H. Bailey. Third 



edition. (London and New York : Macmillan and 



Co., 1895.) 



PROF. MUIR'S neat and presentable volume is 

 the latest claimant upon the indulgence of the 

 agricultural public, the number of readers — and what is 

 more to the point, the number of students — amongst 

 whom is undoubtedly steadily increasing. Commencing 

 with a discussion of the plant, the author speedily falls 

 back upon the soil as the staple of his discourse, though 

 parenthetically he introduces a chapter on plant food in 

 the soil. Then we get the inevitable section on the 

 IJritish geological formations, which has about as much 

 relation to the living art of agriculture as a list of our 

 kings and queens has to a true understanding of English 

 hislor)'. Drainage, irrigation, and other processes for 

 ameliorating the soil are next discussed, and then half a 

 dozen chapters are devoted to the important subject of 

 manures. Implements and machines are next briefly 

 glanced at, and the remainder of the book is occupied 

 by chapters on the chief crops of British agriculture. 

 We believe that, well-worn as the theme is, there is still 

 rtM>m for novelty in the treatment of agriculture as a book 

 subject, but Prof. Muir does not appear to have hit 

 upon iu 



Live-stock constitute the backbone — the sheet-anchor 



NO. 1345, VOL. 52] 



— of British agriculture, and to omit all reference to this 

 indispensable section of our greatest national industry in 

 a book bearing the comprehensive title of the volume 

 under notice, is a blemish upon the work. No one 

 would ever infer from its name that the volume is silent 

 upon the great subject of sheep husbandry, which has 

 become so inextricably — and we may <idd so ad\an- 

 tageously— interwoven with the arable farming of this 

 country. Nor would any one expect, in a book on 

 ".Agriculture, Practical and Scientific,'' to find no 

 allusion to the milk-pail and the cows that fill it, and 

 no mention of the butter and cheese industries. The 

 author recognises that agriculture embraces " the breed- 

 ing, feeding, and man.igement of all kinds of farm live- 

 stock," but it is not till the reader begins perusing its 

 pages, that he learns that the work " will not attempt to 

 deal with" this part of the subject. In this matter, the 

 author had nobody but himself to please, and all we 

 venture to say is that the title of the volume should 

 have fitted its contents. .A work on "agriculture" that 

 ignores live-stock might fairly be compared to a treatise 

 on chemistry that made no mention of carbon. 



The part of the work that is best done is that relating 

 to crops, and had Prof Muir chosen to confine himself 

 to this branch of farming, he would not have acted un- 

 wisely. His skilful treatment of this section of the sub- 

 ject serves to revive the recollection of John Wilson's 

 admirable work in the middle of the century. But the 

 most important cropping of all — that of grass land -is 

 inade(.|ualcly treated, though it is abundantly evident, 

 from the few pages allotted to this subject, that the author 

 might usefully have given more space to it at the expense 

 of one or two perfunctory chapters which would not have 

 been missed. The processes of hay-making and ensilage 

 are well described, yet here again the idea arises that 

 the author felt he was approaching his limits, and the 

 result is that he appears to exercise a restraint 'which 

 we feel sure has operated to the disailvantage of the 

 reader. .A feature of the work that will be much appre- 

 ciated is that it reproduces in a handy form many of the 

 tabular statements that have from time to time been 

 published in the Journal of the Royal Agricultural 

 Society of England. Three dozen illustrations accom- 

 pany the text, and those of seeds are particularly note- 

 worthy for iheir fidelity. 



Commending the book, then, for its triistwoilliy tioal- 

 ment of farm crops, we may notice one or two features 

 that seem to call for criticism. The index is sometimes 

 relied upon for the introduction of terms not given in 

 the text. Thus, "nitrification " is indexed as dealt with 

 at page 25, turning to which the reader finds the process 

 described, but no name given to it, unless perchance the 

 term "oxidation " is inadvertently used instead. Other 

 similar cases occur. .A highly important subject to 

 farmers, the temperature of germination, is surely 

 awarded scant treatment when it is dismissed in the 

 brief paragraph : "The temperature most favourable to 

 germination varies in the seeds of different plants." 

 Such frequent recourse is made by the author to the 

 work of Lawes and C.ilbert, that it is regrettable he did 

 not imitate the consistency with which they employ the 

 term "nodules" to denote the outgrowths on the roots of 

 papilionaceous plants. The repeated use of the word 



