478 



NATURE 



[December 31, 1914 



These have often solid centres like those in his 

 Fig. 5, plate i ; the bands also resemble the irregular 

 septa in his Atikokania. Without any traces of 

 spicules it seems to me very doubtful indeed that these 

 bodies have any organic origin, especially as it seems 

 clear that changes in rocks after deposition lead some- 

 times to the formation of tubes. If my conclusions 

 are correct, this in the Fuhvell coralloids is certainly 

 a very common development in the almost universal 

 rod formation there. The change appears to be the 

 result of the adherence of small circular groups of 

 rods around a central canal; with so much of such 

 material— there are at least two square miles of it 

 some 130 ft. thick — the cause, whatever it may be, 

 seems unconnected with either erosion, hydration, 

 dolomitisation, metasomatosis, or organic remains. 



I have also seen tubes of this kind in a few other 

 calcareous rocks, but the most common banded forma- 

 tion (probably allied to the septae in Dr. Walcott's 

 specimens) is seen in weathered mortar found in the 

 shadv parts of old buildings, especially those situated 

 near^the coast. George Abbott. 



■2 Rusthall Park, Tunbridge Wells, November i8. 



form interesting alike to the specialist and the 

 general reader. In showing what is known and 

 what has yet to be found out about the habits 

 of our birds, and in laying stress on the scientific 

 problems which underlie the facts, the work stands 

 alone in giving to the serious student of bird-life 

 starting-points for further research. Though not 

 professing to do more than supply summaries 

 of the geographical distribution of all the species, 

 the work claims to give recent information under 

 this head which is not to be found in any other 

 book on British birds. 



It would be unjust to the contributors to these 

 volumes if the impression arose that they had 

 been merely content to compile the observations 

 of others. For while it is true that in more than 

 one case contributors to this book have found 



When your letter of November 23, 19 14, enclosing 

 a note by Mr. George Abbott on the silicified struc- 

 tures described in Memoir No. 28 of the Geological 

 Survey of Canada as Atikokania laivsoni, reached rpe 

 on December 8, I had on my table a copy of Nature 

 of January 29, 1914, containing the note on "Zonal 

 Structure in Colloids," by Mr. Abbott. Prior to meet- 

 ing with this article, I did not know of the remark- 

 able structure of the Sunderland Magnesian Lirrie- 

 stone, or I should have certainly directed attention 

 to it. 



During the past summer I made large collections 

 of supposed algal remains from the pre-Cambrian 

 rocks in the Rocky Mountains of Montana. Some of 

 these appear to be of undoubted organic origin. 

 Others appear to be a combination of algal deposits 

 in connection with concretionary consolidation. 



The subject is now under investigation, and in this 

 connection I shall take up the forms that I called 

 Atikokania. With present information I should not 

 be inclined to refer the latter to the sponges or to 

 the Archaeocyathinae. Charles D. Walcott. 



Smithsonian Institution, Washington, U.S.A., 

 December g. 



A HISTORY OF BRITISH BIRDS.^ 



WE have already noticed the first four parts 

 of this comprehensive publication, and the 

 general scope of the work and the plan on which 

 it is carried out need not be more than briefly 

 referred to here. We now welcome the twelfth 

 and concluding section of the work and the last 

 of its attractive and fascinating pages. 



The book claims to be the only existing work 

 which gives an adequate account of the habits 

 of all our species of birds, except those so rare 

 that they cannot be said to have, as British birds, 

 any habits worth describing. These latter are 

 treated shortly at the end of the last volume. 

 It claims also that it brings together from every 

 source, British and foreign, the whole available 

 information on the subject, and presents it in a 



i "The British Bird Book." Edited bv F. B. Kirkman. Sections V — 

 XII. (Lo. don and Edinburgh : T. C. and E. C. Jack, n.d.) Price io.f. 6(/. 

 net, per serti )n. 



'" "fig. 1.— Lapwing's nest. From '■ The British Bird Book." 



themselves in the very unsatisfactory position of 

 having to w^rite about species of which they had 

 little personal knowledge, there is much informa- 

 tion in the book that is the result of direct personal 

 observation, and much, again, of this information 

 could have been supplied only by the contributors 

 and by no one else. Among them we have only 

 to name the Rev. F. C. R. Jourdain, who, in 

 search of eggs, has travelled over so much of 

 Europe and the adjacent countries, and Mr. 

 William Farren, to show how much valuable 

 original observation the editor has had to draw 

 upon among his various contributors. As the 

 editor points out, too, though the bird-man who 

 has concentrated his attention on a few species 



NO. 2357, VOL. 94] 



