Jan. 3, 1884] 



NA TURE 



213 



and Ocean Basins," in which, after giving the views of Ilerschell 

 and Airy, I bring out this idea very prominently, and illustrate 

 it by many diagrams. An abstract of thi-^ ptiper, by Sterry 

 Hunt, was publi-hed in the Canadian A'aiiiralist, vol. iv., 

 '859, p. 293, and reference to it will be found in the " Royal 

 .Society Catalogue," vol. iii. p. 919. 



A very brief outline of the j aper is as follows : — I make two 

 assumptinns : (i) an internal liquid with flo.ating crust ; (2) the 

 crust of continental areas more conductive and therefore cooling 

 and thickening more rapidly than that of oceanic areas. 



It is evident that under these assumptions inequalities 

 would commence first on the under .surface of the crust 

 by additions there, making convexities beneath the conti- 

 nental and concavities beneath the oceanic areas. But by 

 flotation these inequalities on the under side next the liquid 

 would be reproduced on the upper side next the atmosphere, 

 and by this means alone continents would grow continually 

 higher, and ocean beds deeper. Now add to these erosion. By 

 cutting down continents and filling up the seas erosion wou^d 

 tend coistantly to destroy these inequalities, while flotation 

 would tend as constantly to reproduce them. Thus according 

 to this view the continents rise partly by additions beneath and 

 partly ly removal above, and similarly the ocean beds sink 

 partly by increased concavity beneath and partly by additions 

 above. But evidently if unequal thickening should stop, flo'a- 

 tion could only partly restore the inequalities destroyed by 

 erosion. 



Except the absirac' above referred to, the paper was never 

 publi-shed, and in February, 1865, it was destroyed, along v ith 

 much else, by Sherman's army. My reason for not publishing 

 more fully was that I soon became dissatisfied \\ith it ; for about 

 that time the views of Hopkins and Pratt on the solidity of the 

 earth began to attract attention, and I became convinced that 

 dynamical geology must be reconstructed on a basis of a solid 

 eartli. But now that the idea of a sub-crust liquid or semi- 

 liquid layer is becoming prominent (a condition which would not 

 probably interfere with the substantial solidity of the earth in 

 its astr 'Uomical relations), it seemed to me important that this 

 long forgotten paper should be brought forward merely as a part 

 of the history of the subject. 



Now a few words on the subject of the communications referred 

 to in the beginning of this letter. It seems to me that some of 

 your con-espondents have gone too far in regarding unloading by 

 erosion as a cause of elevation. Evidently there must be Fome 

 other and more fundamental cause, or erosion could not act. 

 Evidently erosion can only partly restore an elevation produced 

 by some other cau-e. Erosion is primarily an effect of eleva- 

 tion, only in this a^ in so many other cases the effect may react 

 as a cause, to maintain the elevation. For ex.imple, the Colorado 

 plateau region has been raised since Cretaceous times about 

 20,000 feet, but the maximum general erosion has Leen only about 

 12,000 feet. The erosion has been, therefore, the consequence, 

 not the cause, of elevation, for it is impossible that the cause 

 sho'.ild lie so far behind the effect. I give this one example 

 because it is on so large a scale, but every mountain range 

 furnishes an example of great ere ion as aa effect of elevation 

 produced by other causes. That loading and unloading the 

 crut is a cause of subsidence ai:d elevation there is little doubt, 

 but that there are other and far more important causes is certain. 



Berkeley, Cal, December 3 Joseph LeConte 



Red-deer Horns 



In continuation of my remarks on the eating of shed deer- 

 horns by other deer, I have to add that six shed horns in various 

 stages of erosion have been sent to me from Sutherlandshire. 

 They each bear well defined teeth-marks on the gnawed por- 

 tions, and this leaves little if any doubt that the popular belief 

 that the horns are eaten by deer is founded on fact. The 

 accompanying interesting letter from Mr. James Inglis, which 

 gives the evidence of two experienced stalkers, both most intel- 

 ligent and reliable men, is further confirmation of a curious 

 though m doubt very natural habit of the deer, which finds in 

 the lime-salts of the horn a necessary element of nutrition. You 

 will observe that Inglis believes the deeru.se the molars in eating 

 the bone, and this seems probable enough, as they apparently 

 al.vays begin al the points and eat towards the beam and burr, a 

 method of proceediig by which they can bring portions of the 

 horn within the action of the molars. J. Fayrer 



December 27, 1SS3 



"... I send a few red-deer horns that have been parti.ally gnawed 

 by deer in the forest. I asked the .stalkers to keep a look out 

 and see if they ould find any deer eating horns, and am glad to 

 say that they have been able to put the matter beyond all doubt. 



"Donald McRaesaw with his glass a stag, in Dunrobin Glen, 

 eating a horn ; he went to the place where he saw him eating it, 

 and found it partially eaten. I send it with the others. You 

 will find a ticket on it to distingui-h it from the rest. 



" Duncan McPherson s.iw with his glass a hind, last week, 

 eating a horn also ; he did not find the horn, but he saw her (the 

 hind), quite plainly, w'ith it in her mouth, gnawing away at it 

 near the point. 



" Deer have no incisors in the upper jaw, but they have grinders 

 or molars in both upper and lower jaws, formidable enough 

 to eat any horn, and I have no doubt that it is with their molars 

 that the horns are eaten. 



" A shepherd in the parish of Lairg has a cow that eats all the 

 bones she can find, and goes miles for the-m, and eats them up, 

 shank bones and all ; ribs are eaten easily, and seem to give no 

 trouble whatever. " J.^mes Inglis 



" December 24, 18S3 '' 



On the Absence of Earthworms from the Prairies of the 

 Canadian North-West 



Not by any means the least remarkable of the very notable 

 series of works which Mr. Darwin h.as give-i to the world is that 

 which came last from his pen but a short time previous to his 

 lamented death. Dealing, as it docs, with eftects which, when 

 looked at in the detail, are exceedingly small and insignificant, 

 bu^, when viewed in the aggregate, are shown to be of surpris- 

 ing importance, the "Vegetable Mould and Earthworms" must 

 certainly rank as a most strikingly inlere.ting work. 



It is not my desire to call in question the conclusions at which 

 Mr. Darwin has arrived with regard to the action of earthworms 

 in culiivating the soil, but I wish to piint out that in one exten- 

 sive portion of the earth's surface, to which much attention has 

 of late been directed on account of its agricultural capabilities, 

 earthworms do not exist. I refer to the vast region commonly 

 known as Manitoba and North-West Territories. My friend, 

 Mr. E, E. T. Seton, of Carberry, Manitoba, was the first to 

 point out to me that this enormous country mu^t l)e regarded as 

 forming an exception to Mr. Darwin's generalisations, on account 

 of the total absence from it of every kind of earthworm, and, 

 having lately returned from a visit to Ihnse re.'ions, I can add 

 my tetimony to his in this p.articular, as well as in the matter of 

 the amazing, innate fertility of the soil, which has been the 

 wonder and remark of all travellers for years past, but which, 

 in this case, obvi .u ly cannot be attributed to the action 

 of worms, .sii.ce these do not exi t there. In addition 

 to my own ob-ervations, I have the testimony of num- 

 bers of intelligent settlers, most of whom had been seve- 

 ral years in the country, but all of whom unhesitatingly 

 assured me that such a thing as an earthworm was tmknoun. 

 Further, Mr. Leo Rogers, son of Mr. Thos. Rogers of Man- 

 chester, « ho has spent several years with the engineers of the Cana- 

 dian Pacific Railway, has informed me that ea-thworms are un- 

 known between Winnipeg and the Rockies. This being the case, 

 it does not seem reasonable to suppose that they exist anywhere in 

 the huge territorystill further to the north, and comprising upwards 

 of 3,oco,ooo square miles of land, or something like one third of 

 the entire North American continent, and which may therefore 

 be regarded as forming an exception to Mr. Darwin's statement 

 (p. 120), th.it " Worms are found in all parts of the world, and 

 some of the gc'i-cra have an enormous range. They inhabit the 

 mo t isolated islands; they abound in Iceland, and are knovi'n 

 to exist in the We-t Indies, St. Helena, Madagascar, New 

 Caledonia, and Tahiti. In the Antarctic regions worms from 

 Kerguelen Land have been described bv Ray Lankester, and I 

 have found them in the Falkland Islands. How they reach such 

 isolated spots is at present quile unknown." In connection with 

 the statement (p. 121) that " Worms throw up plenty of castings 

 in the United States," it may be pointed out that the boundary 

 line (the 49th parallel) is to some extent a natural one, from 

 which the rivers run both north and south. Further, I have 

 been assured by friends, and have also seen with my own eyes, 

 that earthworms abound at Toronto and in other parts of Ontario. 

 This being the case, an interesting inquiry arises as to the cause 

 of the absence of worms from the North-West, and I can only 

 suggest two probable reasons — the great cold of winter and the 



