iSo 



NA TURli 



[Fehkuakv 20, 1902 



characler is. Krom the examinalion of some 1500 species I am 

 convinced ihat the character of the medullary rays (which, by 

 the way, are anything but medullary in the secondary wood) is 

 the most constant feature and should form the basis of an 

 artificial key, but it separates the genus Betula, the rays of 

 which are but a millimetre high on a vertical section from 

 AInus, where they may run to inches, and it cuts the Leguminos.v 

 into two halves, one ol which has bold spindle-shaped rays in 

 transverse section (Ulex, Cytisus, i&c), while in the other the 

 rays seem to meander amongst the vessels like so many limp 

 threads (Mimosa, (ileditschia, &c.). 



Nevertheless, a useful key may be constructed by first dis- 

 tinguishing those woods with two kinds of rays (many Cupuliferie) 

 from those having but one. The latter then fall into two groups, 

 one having rays which have intervals between them of not less 

 than the transverse diameter of the largest pores present, the 

 other conversely having the intervals between the r.ays never 

 greater than the pore-diameter, i.e. the rays diverge and run 

 round or avoid the pores. These two types of rays are very 

 clearly marked and have quite difterent aspects. The arrange- 

 ment of the vessels or pores can then be usefully employed, as 

 the concentric radial, tree-like or undulating groups, or uniform 

 distribution of the pores is very constant in many genera, as are 



also the equally varied forms assumed by the soft-tissue (wood- 

 parenchyma), which comes next in order of importance. It 

 would be out of place here to go into further detail, and it need 

 only be pointed out that by following this sequence all members 

 of the same genus except the aberrant forms fall together into 

 the same ultimate group, which is not the case with Nordlinger's 

 or any other key that I have used. 



Many groups, or even whole genera, are so similar in structure 

 that (heir species can only be distinguished by long acquaintance, 

 <r..4'. Fraxinus, Acer, i.\:c. , and it is then necessary to have 

 recourse to other features, such as the specific gravity, colour, 

 smell, taste, hardness, behaviour with certain reagents, colour of 

 their solution with water and alcohol, iic. Frequently these are 

 so pronounced that a single feature may be sufficient to describe 

 a species, a<, for example, the ofiensivelj powerful cheese-like 

 smell of Goiipia tomcntosa and the flinty hardness of Lignum 

 vitae, hence 11 has often been urged that if a wood can be so 

 readily identified by such simple means, why employ a more 

 complicated and less accessible method. No one underrates 

 obvious characters, but there are thousands of species, hundreds 

 of which are employed in the arts, that have no pronounced 



NO. 1686, VOL. 65] 



feature (if this kind to distinguish them. The value of the 

 anatoinical characters to the systematic botanist and to the trader 

 is, however, in inverse proportion. The closer the resemblance 

 in structure between the members of the same group the stronger 

 the claim for a place in classification. On the other hand, the 

 greater the dissimilarity the easier becomes their discrimination for 

 commercial purposes. 



A 



CONFERENCE ON SCHOOL GARDENS. 

 CONFF,UENCE on school gardens was held under the 

 auspices of the Berkshire County Technical Education 

 Committee at Reading College on Saturday. Mr. T. G. Hooper, 

 one of His Majesty's inspectors of schools, read a paper on 

 "School Gardens in England and in Germany," giving an 

 account of those he has helped to institute in this country and 

 others which he visited on the Continent. He dwelt, too, upon 

 the provision made in Germany at the Pomological Institute for 

 training elementary teachers, and one of his must interesting 

 points %vas with regard to them. They are not, as here in 

 England, expected in return for tuition, maintenance and travel- 

 ling expenses, to attend courses of instruction during well- 

 earned holidays, but ihey have the additional privjlrge of 

 working at the Institute during term time, a substitute being 

 paid to take their duty. 



English school gardens, though at present comparatively few 

 in number, are on all sides acknowledged 10 be the most 

 practical yet instituted. Except in the case of those attached 

 to continuation schools, no attempt must be made to utilise 

 them for the technical teaching of gardening or oiherwise than 

 as mere training, mental and manual. A point obvious enough 

 that was touched upon was that inspectors of schools should 

 know something of horticulture if they are to report on school 

 gardens and these are to be instituted in larger numbers. The 

 importance of it is that, with very few exceptions, the inspectors 

 are not at all well versed in the subject. County Councils 

 cannot spend money directly upon elementary schools, but 

 training of teachers they can arrange for, they can hold con- 

 ferences such as the one here discussed, and their horticultural 

 instructors may, and do, without breaking the law, give advice 

 on the la)ing out of school gardens. Mr. J. C. Medd, in the 

 course of his remarks, alluded to the Nature-Study Exhibi- 

 tion, with a view to holding v\hich in London during next 

 summer an association has just been formed. .-Kt this, which 

 if it comes about will be greatly due to Mr. Medd's efforts, 

 garden produce that may be in the proper condition at the 

 time will no doubt be welcomed. Sir John Cockburn, lately 

 Premier and Mini^ter for Education in South Australia, is the 

 chairman of the executive committee. Sir John, speaking at 

 the Conference, alluded to "Arbor Day," upon which every- 

 one in the antipodes who can plants a tree. The idea, one 

 might say, is borrowed from America and is a very good one. 



The difiiculiy of getting proper time for practical work was 

 also touched upon by Sir John Cockburn, who said that, although 

 one hour was all he could obtain at first, neveriheless, before 

 he left South Australia, schools had been started in which only 

 half the time was devoted to theoretical instruction. 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE. 



Oxi'OKi). — At the 232nd meeting of the Junior Scientific 

 Club on Wednesday, February 12, two papers were read, viz. 

 " Colour and Chemical Composition," by Mr. S. A. lonides, 

 Balliol College, and "The Centrosome," by Mr. A. D. 

 Darbishire, Balliol College. 



By his will. Sir J. H. (iilbert, F. R.S., who was Siblhorpean 

 professor of rural economy from 1S84-90, and who died on 

 December 23, 1901, bequeathed the portrait of himself by his 

 brother, Josiah Gilbert, to the University of (Jxlord, io be 

 placed in the library of the Sibthorpean professor of rural 

 economy. 



Dr. F. T. Titot n.iN, F. U.S., of Trinfiy College, Dui.lin, 

 has been appointed t,)uain professor of physics in University 

 College, London, in succession to Prof. H. L. Callendar, F. R.S. 



Dk. W. II. Wii.i.cox has been appointed deputy lecturer in 

 hygiene at Bedford College for Women, on the resignation of 



