I IO 



NATURE 



[July 27, 191 1 



exceptionally interesting native flora, and with this 

 object he has, in addition to his various official re- 

 ports, contributed from time to time popular botanical 

 articles to different local journals. The material for 

 several of these articles has been worked up into the 

 more homogeneous ecological account now published 

 by the Government of New Zealand for the benefit of 

 private individuals and for instruction in schools. 



The wealth of botanical treasures is truly great. 

 Thus the forests comprise mixed forests — in which the 

 ancient kauri pine, Agathis australis and Beilschmiedia 

 tarairi, are conspicuous — and pure forests of Podo- 

 carpus dacrydioides and Nothofagus. The mixed 

 forests are the homes of abundant lianes— to mention 

 only species of Metrosideros, the liliaceous Rkizopogon 

 scandens and Lygodium reticulatum — many tree ferns 

 and epiphytes. No less interesting are the shrubs, 

 chief amongst which are the subalpine species of 

 Olearia, Cassinia, and Veronica, while the manuka. 

 Leptospermum scoparium, and allied species plav an 

 important part in the physiognomy of the native 

 heaths. Then again the alpine meadows are rich in 

 floral gems, notably species of Euphrasia, Ourisia, 

 Celmisia, and Ranunculus. Amongst plant curiosities 

 the vegetable sheep, Raoulia eximia, is the most 

 unique. 



In addition tn the ecology, chapters are devoted to 

 an account of the early explorers, naturalised plants, 

 the stories of four common plants— New Zealand flax, 

 manuka, Fuchsia, and Cordyline australis — and plant 

 cultivation. The few examples noted above will serve 

 to indicate how rich and unique is the New Zealand 

 flora; Dr. Cockayne's treatment is fully equal to his 

 subject, and one could only wish that he had much 

 more space to enter into greater detail. The numerous 

 illustrations, although imperfectly reproduced, contri- 

 bute a better realisation of the plant scenery. 



Dc la Mithode dans }cs Sciences. Dcuxieme Serie. 



by B. Baillaud, L. Bertrand, L. Blaringhem, E. 



Borel, G. Lanson, L. March, A. Meillet, J. Perrin, 



S. Reinach, and R. Zeiller. Pp. iii + 365. (Paris: 



Felix Alcan, 1911.) Price 3.50 francs. 

 The first series of studies in the methods of science 

 by distinguished French writers was reviewed in 

 Nature on September 23, 1909 (vol. lxxxi., p. 361). 

 The present volume has the same general character- 

 istic-., though the point of view is more technical and 

 less philosophical. The following branches of science, 

 which were not dealt with in the former volume, re- 

 ceive attention— astronomy, physical chemistry, 

 geology, botany and palaeobotany, archaeology, 

 literary history, linguistics, and statistics. The 1 

 should assist in providing the reader with a broad 

 general view of scientific methods, and help to correct 

 the narrowness which may result from a too exclusive 

 absorption in a restricted field of scientific investiga- 

 tion. 



\ 



Essays in h I hemistry. By Sir Edward 



Thorpe, C.B., F.R.S. Third edition. Pp. xii + 601. 



(London: Macmillan and Co., Ltd., 1911.) Pries 

 12s. net. 



Previous editions of this valuable work havi been 

 reviewed in these columns al seme length, the first in 



our issue for April 12, iSo.| (vol. xlix., p. 551), and the 



second in that ol August [4, 1 (vol lxvi., p. 365). 



The present edition differs from the last in in.! 

 the memorial lecture on Julius Thomsen delivered to 

 tlie bellows of the Chemical Societ) en February 17. 

 We also notice an addendum to the lite oi 

 Prot. ' annizzaro, who died at Rome on 



May 10, into. 



2i :s. v,.r.. 87] 



School Planning at Home am! Abroad. By William 

 H. Webb. Pp. 42. (London : The Sanitary Pub- 

 lishing Co., Ltd., 1911.) Price is. net. 

 At the annual congress of the Royal Sanitary Institute, 

 held in September last at Brighton, Mr. \Yebb read 

 a paper on "Large Public Elementary Schools in 

 Town Districts." The paper is here published in book 

 form, and illustrated by plans and other diagr; 

 Mr. Webb's inquiries respecting the characteristii 

 school buildings in various parts of Europe and 

 America enable him to provide those responsible for 

 the design of new schools with manv useful hints. 



LETTERS TO THE EDITOR. 



[The Editor does not liold himself responsible for opinions 

 expressed by his correspondents. Neither can he undertake 

 to return, or to correspond with the writers of, rejected 

 manuscripts intended for this or any other part of Nature. 

 No notice is taken of anonymous communications.] 



The Rearirg of Sea Urchins. 

 I enclose a photograph which may interest your 

 readers. It is one of a water-colour painting of a sea- 

 urchin, magnified 4 diameters, which has been reared in 

 my laboratory by Dr. Cresswell Shearer. It is a hybrid, 

 a cross between Echinus milearis (male) and E. esculentus 

 (female), both obtained from the Plymouth Marine Labora- 

 tory, fhe cross was effected in the early part of March 

 last. It was kept in thoroughly aerated seawater foi 



-'■in.' 1 ime, but has Fi 1 1 he Let threi months been li 

 in a bell-jar with part of an old crock covered by worm 

 tubes, without the water being aerated in any way. It 

 generally shelters in the day time under the crock. When 

 disturbed, it moves actively awa) from He light, ami still 

 appears thoroughly healthy. It shews what mai bi dom 

 in an inland laboratory with simple appli 



J. Stanley Gardiner. 

 Zoological Laboratory, Cambridge. Jul} to 



Absorption Markings in " K '' Spectroheliograms. 

 Mr. i lis in Nature of May 1 1 



me to think that pe--il,lv an essential difference in the 



method employed I producing original w fo 



journalistic purposes might go far towards explaining the 

 difference of definition and richness of detail in M. 

 m Ires' plates. Vnyhow, we are now assured that the 

 Kodaikanal negatives show in the main the same strui - 

 tures as those taken at Meudon. Yet if the former 

 admittedly permit such a great amount of K. radiation to 



