February 14, 1890.] 



SCIENCE. 



1 1 1 



species. Everywhere we find the same variations at the same 

 stages, differing only in size, never in position. We extend the 

 comparison to a widely separate phylum, and find the same 

 pattern in a similar process of evolution. Excepting in two or 

 three side-lines, the teeth of all the Mammalia have passed 

 through closely parallel eaiiy stages of evolution, enabling us to 

 formulate a law : The new main elements of the crown make 

 their appearance at the fii-st points of contact and chief points of 

 wear of the teeth in preceding periods, Wliatever may be true 

 of spontaneous variations in other parts of the organism, these 

 new cusps arise in the perfectly definite lines of growth. Now, 

 upon tlie hypothesis that the modifications induced in the organ- 

 ism by use and disuse have no directive influence upon varia- 

 ti>3ns, all these instances of sequence must be considered coinci- 

 dences. If there is no causal relationship, what other meaning 

 can this sequence have? Even if useful new adjustments of 

 elements already existing may arise independently of use, why 

 should the origin of new elements conform to this law? Grant- 

 ing the possibility that the struggle for existence is so intense 

 that a minute new cusp will be selected if it happens to arise at 

 the right point, where are the non-selected new elements, the 

 experimental failures of nature? We do not find them. Paleon- 

 tology has, indeed, nothing to say upon individual selection, 

 but chapters upon unsuccessful species and genera. Here is a 

 practical confii-mation of many of the most forcible theoretical 

 objections which have been urged against the selection theory. 



Now, after observing these principles operating in the teeth, 

 look at the question enlarged by the evolution of parallel species 

 of the horse series in America and Europe, and add to the de- 

 velopment of the teeth what is observed in progress in the feet. 

 Here is the problem of correlation in a stronger form even than 

 that presented by Spencer and Romanes. To vary the mode of 

 statement, what must be assumed in the sti'ict application of the 

 selection theory ? (o) That variations in the lower molai-s corre- 

 lated with coincident variations of reversed patterns in the upper 

 molars, these with metamorphoses in the premolars and pocket- 

 ing of the incisor enamel ; (b) all new elements and forms, at 

 fii"st so minute as to be barely visible, immediately selected and 

 accumulated; (c) in the same individuals, favorable variations 

 in the proportions of the digits, involving re-adjustments in the 

 entire limbs and skeleton, all coincident with those in the teeth ; 

 (rf) finally, all the above new variations, con-elations, and re-ad- 

 justments not found in the hereditary germ-plasm of one period, 

 but arising fortuitously by the union of different straiiis, ob- 

 served to occur simultaneously and to be selected at the same 

 rate in the species of the Rocky Mountains, tlie Thames valley, 

 and Switzerland. These assumptions, if any thing, are under- 

 stated. Any one of them seems to introduce the element of the 

 inconstant; whereas in the marvellous parallelism, even to 

 minute teeth-markings and osteological characters, in all the 

 widely distributed fonns between Hyracotherium and Eqiius, the 

 most sti'ikiug feature is the constant. Viewed as a whole, this 

 evolution is one of uniform and uninterrupted progression, taking 

 place simultaneously in all the details of structure over great 

 areas. So nearly does race adaptation seem to conform to the 

 laws of progi-essive adaptation in the individual, that, endowing 

 the teeth with the power of inmiediate re-active gi'owth like 

 that of the skeleton, we can conceive the transformation of a 

 single individual from the eocene five-toed bunodont into the 

 modern horse. 



The special application of the Lamarckian theory to the evolu- 

 tion of tlie teeth is not without its difiiculties, some of which 

 have been pointed out to me by Mr. E. B. Poulton. To the ob- 

 . jection that the teeth are formed before piercing the gum, and 

 the wear produces a loss of tissue, it may be replied that it is 

 not the growth, but the re-action which produces it, wliich is 

 supposed to be transmitted. Again, this is said to prove too 

 much. Why is the gi-owth of these cusps not continuous ? This 

 maybe met in several ways: fii-st. in the organism itself these 

 re-actions are least in the best adapted structures, a proposition 

 which is more readily demonsti'ated in the feet than in the teeth 

 (moreover, since the resulting gi'owth never exceeds the uses of 

 the individual, there is a natural limit to its ti'ansmission) ; 



second, the growth of the molars is limited by the nuti-itive 

 supply (we observe one tooth or part growing at the expense of 

 another) ; third, in some phyla we do obsei-ve gTowth which ap- 

 pears to lead to inadaptation, and is followed by extinction. In 

 one instance we observe the recession of one cusp taking place 

 Xjari passu with the development of the one opposed to it. 

 These and many more general objections may be removed later ; 

 but they are of such force, that, even granting our own premises, 

 we cannot now claim to offer a perfectly satisfactory explanation 

 of all the facts. 



The evidence in this field for, is still much sti-onger than that 

 against, this theory. To sum up: the new variations in the 

 skeleton and teeth of the fossil series are observed to have a defi- 

 nite direction ; in seeking an explanation of this direction, we 

 observe that it universally conforms to the re-actions produced 

 in the individual by the laws of growth ; we infer that these re- 

 actions are transmitted. If the individual is the mere pendant 

 of a chain (Galton) , or upshoot from the continuous root of 

 ancestral plasm (Weismann) , we are left at present with no ex- 

 planation of this well-observed definite direction. But how can 

 this transmission take place ? If, from the evident necessity of a 

 working theory of lieredity, the 07ms prdbandi falls upon the 

 Lamarckian, — if it be demonstrated that this transmission does 

 not take place, — then we ai'e driven to the necessity of postulat- 

 ing some as yet unknown factor in evolution to explain these 

 pui-posive or directive laws in variation, for, in this field at 

 least, the old view of the random inti-oduction and selection "of 

 new characters must be abandoned, not only upon theoretical 

 grounds, but upon actual observation. 



Reading between the lines of Weismann' s deeply interesting- 

 essays, it is evident that he himself is coming to this conclusion. 

 Henry Fairfield .Osborn. 



AMERICAN ARCHIVES IN SEVILLE.' 



If I could meet the historical students of the Johns Hopkins 

 University or the members of the Maryland Historical Society, 

 lam quite sure, that with the aid of a few photographs which I 

 can find here, and with the aid of a few books to which, as a 

 hurried traveller, I cannot here find access, their interest would 

 be quickly excited in an account of the celebrated -collection of 

 papers pertaining to early American history which I have just 

 visited for the second time. I am not so sure that by means 

 of a letter I can convey the same inij)ression : nevertheless I 

 will try. 



The Alcazar, which is to be compared with, if it does not 

 equal, the Alhambra as a Moorish palace; the Giralda, a 

 magnificent bell-tower, noble in size, proportions, and details, 

 and famous as an observatory in the days of Moorish supremacy; 

 and the Cathedral, which contains a few of the most celebrated 

 works of Murillo, — form a group of buildings which has given 

 renown to Seville, and has drawn the admiring gaze of archi- 

 tects and poets and historians from every part of the civilized 

 world. 



Under the shadow of these world-famous monuments are two 

 edifices' which, in comparison with the three greater structures, 

 hardly arrest the notice of the sight-seeker, though they are 

 buildings which would be noteworthy for their age and dignity 

 in any American city. One of these contains the Columbian 

 Library, founded by Fernando Columbus, son of the great dis- 

 coverer; and the other contains original papers which pertain 

 to the Spanish discoveries in the New World. It is of the 

 second of these remai'kable and world-famous collections that I 

 now propose to write. 



Casa Lonja is the name of the building in which are kept 

 "The Archives of the Indias,'" the title by which Spain has 

 designated from the earliest days until now the papers per- 

 taining to her American discoveries and possessions. For a 

 long period the authorities of this country refused to accept the 

 name "America," and "only yielded to the majority," as a 

 Spanish writer informs us, "when resistance was useless." 



> Letter from President D. C. Gilman, in the Baltimore Sun o£ Dec. 31, 1889, 

 written from Seville, Spain, under date of Dec. 12. 



