HISTORICAL SKETCH. XX^ 



emises, par deux hommes justement celebres, GeofEroy 

 Saint-Hilaire et Goethe." Some other passages scattered 

 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 Eev. Baden Powell, in his 

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

 be more striking than the manner in which he shows 

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

 casual phenomenon," or, as Sir John Herschel expresses 

 it, " a natural in contradistinction to a miraculous 

 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 with admir- 

 able force and clearness. 



Von Baer, towards whom all zoologists feel so pro- 

 found a respect, expressed about the year 1859 (see 

 Prof. Eudolph Wagner, ' Zoologisch-Anthropologische 

 Untersuchungen,' 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 be- 

 fore the Royal Institution on the 'Persistent Types of 

 Animal Life.' Referring to such cases, he remarks, 

 "It is difficult to comprehend the meaning of such 

 facts as these, if we suppose that each species of animal 

 and plant, or each great type of organisation, was 

 formed and placed upon the surface of the globe at 



