July 21, 1911] 



SCIENCE 



89 



endyma. These defects were pointed out by 

 me in 1899,'* but in the present paper they are 

 of interest mainly as neither corrected nor 

 even alluded to in any of the reproductions of 

 the figure known to me. 



The figure and description are given on p. 

 876 of the protocols of the committee (of the 

 Anatomische Gesellschaft) on anatomic 

 nomenclature in the fasciculus dated March 

 20, 1894; these protocols were edited by W. 

 Krause. 



But in the following year, in the final re- 

 port," commonly known as the " B !N A," 

 supervised and explained by His himself, the 

 same figure appears on p. 161 as " Median- 

 durchschnitt durch ein fotales menschliches 

 Gehirn aus dem dritten Monat." It may be 

 conjectured that there had occurred an inad- 

 vertent repetition of the legend under the fig- 

 ure on the opposite page (where, however, the 

 first word is " Medianschnitt ") ; but it is not 

 easy to understand how so self-evident an 

 error could escape the other members of the i 

 committee. 



With the original correct designation of 

 " adult " the figure was reproduced in 1897 by 

 van Gehuchten (Anatomie du systeme nerveux 

 de I'homme, second edition, Fig. 17), and in 

 1899 by L. F. Barker (The Nervous System 

 and its Constituent Neurones, Fig. 92). 



But in 1901 the identical figure, reduced 

 about one third, was employed by Barker^" 

 and described as a " Median section through 

 a human foetal brain of the third month, after 

 His, 1892" [probably 1893 was meant]. 



'* Comments upon the niesal [median] aspect of 

 a human brain as published by His and reproduced 

 by him and others. Asso. Amer. Anatomists, Pro- 

 ceedings, 1899, pp. 23-24. 



'" ' ' Die anatomische Nomenclatur. Nomina 

 anatomica, Verzeichniss der von der Anatomischen 

 Gesellschaft auf ihrer IX. Versammlung in Basel 

 angenommen Namen. Eingeleitet und im Ein- 

 verstandniss mit dem Eedactionsausschuss erlaii- 

 tert von Wilhelm His. ' ' Archiv fiir Anatomie und 

 Physiologie. Anat. Abth., Supplement Band, 

 1895. O., pp. 180; 27 figs., 2 plates, 1895. 



™ Buck's "Reference Handbook of the Medical 

 Sciences, ' ' second edition, Vol. 2, Fig. 939. 



Students and lay readers might easily be 

 confused or actually misled by the discrepan- 

 cies indicated above. As yet no explanation 

 or expression of regret has been encountered 

 by me. Fitting opportunity would seem to 

 have been provided for Professor His in his 

 article on nomenclature in the Anatomischer 

 Anzeiger, Vol. XII., October 30, 1896, and for 

 Dr. Barker in his " Anatomical Terminology 

 with special reference to the B N A," 1907.'' 



The injuriousness of an uncorrected error 

 depends not alone upon its intrinsic extent 

 but also upon certain extrinsic conditions, 

 viz., (a) the number and status of those who 

 are interested in the subject and therefore 

 liable to be misled; (b) the publication in 

 which it appeared; (c) the evidence of its un- 

 challenged acceptance by others ; (d) the num- 

 ber of repetitions; (e) the reputation of its 

 originator. To these self-evident propositions 

 should perhaps be added the reminder that one 

 need not himself be inerrant in order to point 

 out imperfections in another. 



The desirability of the explicit correction of 

 errors under some circumstances has now, 

 I trust, been indicated by example as well as 

 by precept. Bdrt G. Wilder 



Ithaca, N. Y., 

 April 6, 1911 



SPECIAL AETICLES 



THE SINGLE CYCLE DEVELOPMENT OF THE GRAND 

 CANYON OF THE COLORADO 



Several years ago Davis' called attention 

 to a number of facts which lead him to con- 

 clude that the Grand Canyon of the Colorado 

 has been developed in a single cycle of erosion 

 as contrasted with the two cycles postulated 



^ So far as I know, the ' ' Isthmus rhomben- 

 cephali ' ' was never withdrawn by Professor His 

 or, explicitly, by any of the several who adopted 

 it; see the papers by B. B. Stroud and the writer, 

 Association American Anatomists, Proceedings, 

 1899, and Science, March 16, 1900. 



^"An Excursion to the Grand Canyon of the 

 Colorado," Bull. Mus. Comp. Zoology, Harvard 

 College, XXXVIII., May, 1901. 



