HISTORICAL SKETCH 23 



through M. Lecoq's 'large work, make it a little doubt- 

 ful how far he extends his views on the modification 

 of species. 



The "Philosophy of Creation" has been treated in 

 a masterly manner by the Rev. Baden Powell, in his 

 "Essays on the Unity of Worlds," 1855. Nothing can 

 be more striking than the manner in which he show3 

 that the introduction of new species is "a regular, not 

 a casual phenomenon," or, as Sir John Herschel ex- 

 presses it, "a natural in contradistinction to a miracu- 

 lous process." 



The third volume of the "Journal of the Linnean 

 Society" contains papers, read July 1st, 1858, by Mr. 

 Wallace and myself, in which, as stated in the intro- 

 ductory remarks to this volume, the theory of Natural 

 Selection is promulgated by Mr. Wallace wich admirable 

 force and clearness. 



Von Baer, toward whom all zoologists feel so pro- 

 found a respect, expressed about the year 1859 (see Prof. 

 Rudolph Wagner, "Zoologisch-Anthropologische Unter- 

 •uchungen," 1861, s. 51) his conviction, chiefly grounded 

 on the laws of geographical distribution, that forms now 

 perfectly distinct have descended from a single parent- 

 form. 



In June, 1859, Professor Huxley gave a lecture before 

 the Royal Institution on the "Persistent Types of Animal 

 Life." Referring to such cases, he remarks, "It is diffi- 

 cult to comprehend the meaning of such facts as these, 

 if we suppose that each species of animal and plant, or 

 each great type of organization, was formed and placed 

 upon the surface of the globe at long intervals by a dis- 

 tinct act of creative power; and it is well to recollect 



