4o8 



NA TURE 



[Sept. 17, 1874 



Animals and Coral Islands," by Prof. W. C. Williamson, F.R.S.j 

 "Assyrian Mythology," by Mr. George Smith; two on "The 

 Education of the People," by Prof. \V. K. Cliflbrd ; "Vitality 

 in Men and in Races," by Dr. B. \V. Richardson, F.R.S. ; "A 

 Night at Lord Rosse's Telescope," and "The Pendulum," by 

 Prof. BaU, F.R.S. 



The following candidates have been successful in obtaining 

 Royal Exhibitions of 50/. per annum, each for three years, and 

 free admission to the course of instruction at the following insti- 

 tutions : — (i) To the Royal School of Mines, Jcimyn Street, 

 London : Charles W. Folkard, Lawrence J. Whalley, Alfred N. 

 Peaison. (2) To the Royal College of Science, Dublin : Thomas 

 Bayley, William Fream, Archibald N. McAlpine. 



Mr. Ramsay Wright, M.A., B.Sc, Assistant to the Pro- 

 fessor of Natural History, Edinburgh University, has been 

 appointed to the Chair of Natural History, University College, 

 Toronto. Mr. Wright succeeds Prof. Alleyne Nicholson, now 

 of the Newcastle College of Science. 



Prof. E. S. Holden, U.S. Navy, forwards us a letter from 

 Mr. H. G. Wright, dated San Bernardino, Cal., Aug. 2, 1S74, 

 describing a small lake or pond in New Hampshire having two 

 outlets, and with which he has been perfectly familiar from boy- 

 hood. "Neither of the outlets," the writer states, "ever dries 

 up, and each of them discharges more water than enters through 

 the only visible feeder. The pond covers, say, fifteen acres ; it is 

 shallow, with muddy bottom, with boulders in places, the sur- 

 rounding land being largely made up of granite ledges and 

 boulders. The outlets are at opposite ends of the pond — one 

 descending rapidly 150 feet soon after leaving the pond, the other 

 passing through a boggy swamp and then a meadow, after which 

 it also descends rapidly. The only feeder is very small, and quite 

 dries up in summer." 



Under the title of "Society for the Publication of Tracts 

 relating to the History and the Geography of the Latin East," an 

 association has been formed in France to supplement the work of 

 the Academy of Inscriptions. Notwithstanding the labours of the 

 latter body, there still exists in the public depositories of various 

 European countries, a large mass of unedited materials relating 

 to the " Latin East," — the kingdoms of Jerusalem, Cyprus, and 

 Armenia, the principalities of Antioch and Achaia, and the Latin 

 Empire of Constantinople. It is for the purpose of unearthing 

 and publishing such material that the French society has been 

 formed. It will be composed of forty titular members and 350 

 subscribing associates ; from among the former a committee of 

 publication will be selected, and the members of both classes 

 may be either French or foreign. Two volumes will be published 

 animally, along with a phototypographic reproduction of veiy 

 rare or unique matter ; to the latter titular members alone are 

 entitled. The collection will be entitled " Bibliotheque de 

 rOrient Latin," and will consist of a Historic Series, a Geo- 

 graphical Series, and a Poetical Series. They will be published 

 after the style of the "Chronicles and Memorials of Great 

 Britain." Titular members pay fifty francs a year, and sub- 

 scribers only fifteen. 



The additions to the Zoological Society's Gardens during the 

 past week include a Serval {fdis so-ual) from West Africa, pre- 

 sented by Mr. Spencer Shield; a Cinereous Sea Eagle [Ilaliacliis 

 albkUli) from Norway, presented by Mr. W. J. Sadler ; two 

 Peregrine Falcons ( Falco pcregriniis) from Europe, presented by 

 Mr. Herbert W^od ; a Macaque Monkey {Macacus cyiioiiiolgiis) 

 from India, presented by Mr. P. T. Wharton ; a Crested Pigeon 

 (Ocy/hn/>s /i>///c>/,-s), two Graceful Ground Doves [Geopdia 

 cuncata), hatched in the Gardens ; two Green Fruit Pigeons 

 (Car/'Oj>/ia!;a sykalka) deposited. 



NOTES ON THE NEW EDITION OF MR. 

 DARWIN'S WORK ON THE STRUCTURE 

 AND DISTRIBUTION OF CORAL REEFS 



(1874.) 



T\/r R. DARWIN, in the new and much improved edition of 

 his work on Coral Reefs, mentions some points in the 

 subject, on which he still finds reason to differ from the writer. 

 I think that with regard to one or two of these points he has 

 not fully understood my views ; and, as to the others, that the 

 arguments and facts which I have brought out have not received 

 all the consideration they may deserve. A review of some state- 

 ments in his work may, therefore, be profitable. I follow the 

 order of his criticisms as briefly stated in the first half of his 

 Preface. 



1. The second sentence of the Preface is as follows : — 



" In this work [Dana's Corals and Coral Reefs] he [the author] 

 justly says that I have not laid sufficient weight on the mean 

 temperature of the sea in determining the distribution of coral 

 reefs ; but neither a low temperature nor the presence of mud- 

 banks accounts, as it appears to me, for the absence of coral 

 reefs throughout certain areas ; and we must look to some more 

 recondite cause." 



The first two clauses of this sentence are true — the but between 

 them being removed, as it may lead some readers to suppose the 

 alternative mine. Yet Mr. Darwin's work does not show that 

 even now he appreciates the influence of oceanic temperature oii 

 the distribution of coral reefs. In his discussions on the dis- 

 tribution of reefs, and the causes limiting the same, this agency, 

 the chiefest with marine life, both for depth and surface, ac- 

 cording to all zoologists, is scarcely mentioned. There is one 

 allusion to the subject on p.age Si. Mr. Darwin says : " I at 

 first attributed this absence of reefs on the coasts of Pcra and 

 of the Galapagos Islands to the coldness of the currents from the 

 south, but the Gulf of Panama is one of the hottest pelagic 

 districts in the world ;" and a note is added, giving some sea 

 temperatures of the region referred to. Thus the cause is set 

 aside even for the se.as along the Peruvian coast, although the 

 mean winter temperature of the water there is lower than exists 

 in any reef region in the w'orld, and is therefore sufficient of 

 itself to exclude reefs. The fact that there are only small 

 patches at Panama, where the temperature is tropical, does not 

 annul the fact that the seas of Peru and the Galapagos are too 

 cold for corals. Where temperature excludes, there is no use in 

 discussing other unfavourable conditions. 



The causes limiting the growth and distribution of reef-making 

 corals and coral reefs, which I have discussed and applied in my 

 work, are sei'cn in number : — 



(I.) Marine temperature. 



(2.) Fresh and impure waters from the entrance of large rivers 

 and muddy bottoms. 



(3.) Deposition of sediment borne by rapid tidal currents. 



(4.) The depth of water along coasts exceeding 100 feet, that 

 is, exceeding the depth to which reef-corals may grow — a com- 

 mon condition along bold coasts, and often explaining, as I have 

 found, the contrasts between the reef-bordered and open coasts 

 of the same island. 



(5.) Exposure to the heat of submarine volcanic eruptions (pp. 

 299-317)- 



(6.) The progressing coral island subsidence too rapid for the 

 polyps to keep the reef well at the surface, if at all (p. 270) : 

 which cause may lead, in atoll seas, to very narrow fringing 

 reefs ; to small sizes in coral atolls, and a more or less complete 

 obliteration of the lagoon ; and to a submerging of the coral 

 island beneath the surface ; or finally, to a complete disappear- 

 ance of the island (pp. 332, 369). 



(7.) The direction and temperature of oceanic currents (p. 112) : 

 this cause accounting for the non-distributiun of Central Pacific 

 species of corals to the Panama coast, and the paucity of species 

 there, with the absence of the large Astra;a group ■ and the 

 Madrepores. 



On this last point I say in explanation, on page 112 : "Owing 

 to the cold oceanic currents of the eastern border of the Pacific 

 — one of which, that up the South American coast, is so strong 

 and chilling as to pusli the southeni isocryme [the line passing 

 through points of equal mean oceanic temperature for the coldest 

 month of the year] of 6S^, the coral sea boundary, even beyond 

 the CJalapagos, and north of the equator — the coral-reef sea, just 

 east of Panama, is narrowed to 20°, which is 36° less of width 

 than it has in mid-ccean ; and this suggests that these currents. 



