174 Professor Owen^ on the [Jan. 27, 



surface of its electrode in a similar manner, escaping from it in 

 tremors ; the matter which it carries along with it being broken up 

 into strata, as a liquid vein is broken into drops.* 



[J. T.] 



WEEKLY EVENING MEETING, 



Friday, January 27, 1860. 



Sir Henry Holjland, Bart. M.D. F.R.S. Vice-President, 

 in the Chair. 



Professor Owen, D.C.L. F.R.S. 



FULLEHIAN PROFESSOB OF PHYSIOLOGY IN THE KOYAL INSTITtTTION. 



On the Cerebral System of Classification of the Mammalia, 



The speaker commenced with a brief review of the principal systems 

 which naturalists had proposed for the Classification of the Mammalia, 

 dwelling more particularly on the following, viz. : — that which, on the 

 ground of certain generalisations in the ' Historia Animalium,' had 

 been attributed to Aristotle ; on the scheme published by Ray, in his 



* Synopsis Methodica Animalium Quadruped uum, 1693 ' ; on the 

 classification adopted by Linnaeus in the 12th edition of the ' Systema 

 Naturse, 1766'; and on that in the 2nd edition (1829) of Cuvier's 



* Regne Animal.' 



The Aristotelian generalisations on the structures and characters 

 of the locomotive organs, as well as those on the dentition, of the 



* Zootoka,' had continued to be used as the groundwork of the primary 

 division of the mammalian class to the time of Cuvier. The chief 

 merit of Ray's system was its exemplification of the principle of the 

 subordination of characters, or of their different values as applicable 

 to groups of different degrees of generalisation. The great step in 

 advance made by Linnaeus, was his accurate definition of the class, and 

 his perception of the significant outward character which suggested the 

 appropriate term which the class has since retained. 



Cuvier, adopting the Linnaean primary divisions, ' Unguiculata^ 



* Ungulata,' and * Muticata/ or ' Cetacea, ' subdivides them into more 

 naturally defined orders, according to various characters afforded by 

 the dental, osseous, generative, and locomotive systems, which his great 

 anatomical knowledge had made known to him. 



That heterogeneous order which Linnaeus — prepossessed in favour of 

 the easily recognisable outward character by which he distinguished the 

 fc 



* Mr. Gassiot has shown that » single discharge of the Leyden jar produces the 

 stratification. May not every such discharge correspond to a single draw of a 

 violin bow across a string ? 



