DR. WALTER CHARLTON. 507 



rect idea could be imparted of the extent and worth of the 

 collection. 



In indicating the progress of " Method," however, it is 

 necessary to go back a little. We have seen that Aristotle 

 had three orders of Testacea, Univalves, Bivalves, and the 

 Turbinated, but the class itself and tljese divisions were 

 loosely defined ; and the same vagueness is to be found in 

 the writings of those authors who followed his method. 

 Deshayes appears to consider Wotton as forming an excep- 

 tion, and, in speaking very favourably of his work, " De 

 Differentiis Animalium," published so early as 1552, he says 

 he was the first to lay the foundation of the comparative 

 natural history of animals, and to conceive the happy idea of 

 separating them into groups from an appreciation of their 

 dissimilarities.* But, perhaps, Dr. Walter Charlton, Physi- 

 cian in Ordinary to Charles I. and II., was the first who had 

 a full conviction of the importance of system ; although 

 his attempt to arrange the Mollusca is very faulty.-)- The 

 Limaces he places with apodous insects ; and aquatic animals 

 being divided as usual into the sanguineous and exsanguine- 

 ous, the remaining molluscans are arranged under two classes 

 viz., the mollia or molluscula and the testacea. The first 

 embraces all the cuttles and the Lepus marinus or Aplysia ; 

 the second, the shelled tribes, whose primary sections are 

 the same as those of Aristotle's, while his genera, usually 

 without a definition, rest on characters of little or no value. 

 Jean-Daniel Major, Professor of Practical Medicine in the 

 University of Kiel, in the dutchy of Holstein, was the next 

 to make the attempt (1675), which is pronounced by two 

 critics, to whose opinion much deference has been shown, to 

 be "infinitely too complicated and ramifying to admit of 

 any useful application. "J Sibbald, Grew, Bonanni, Lister, 

 Langius, Hebenstreit, Tournefort, D'Argenville, and Klein 

 are the principal who followed in their wake ; but it is 

 evident that they had all entered on their task without a 

 previous study of what the real object and use of method 



* Deshayes, Trait. Elem. i. 38. 



t Onomastikon Zoikon, Lond. 16681671, 4to. Charlton was born in 

 1619 ; made M.D. in 1642 ; and soon afterwards physician in ordinary to 

 Charles I., "he being then observed by those who knew him, to set an high 

 value upon his own worth and parts ;" he was also physician in ordinary to 

 Charles II. ; and in 1689 was chosen President of the College of Physicians. 

 He retired about 1691 to the Isle of Jersey, ' a learned and an unhappy man, 

 aged and grave, yet too much given to romances." Wood. Athen. Oxon. 

 ii. 1112. 



$ We have not seen Major's work, but the view of the system given in 

 D'Argcnville's Conchyliologie, p. 112, confirms what is said in the text. 



