68 Bulletin American Museum of Natural History. [Vol. XXVII, 



preconceived scheme, a procedure resulting in the wide separation of genera 

 obviously related. 



He protests also against the blind following of the character of one organ 

 or set of organs in the definition of orders and genera, and he cites examples 

 (/. c, p. xv) to prove that animals differing in many essential characters may 

 yet show close resemblances in certain organs; that is, he recognizes that 

 analogical resemblances should not be used to connect otherwise unrelated 

 organisms. 



Dumeril's classification is based upon that of Cuvier and Geoffroy, with 

 certain modifications "which seemed to help the progression of the system 

 [i. e., in regard to the natural sequence of the genera]," especially in the 

 rodents, marsupials, "Amphibies," and Cetaceans. 



The })ur])ose of the section on the mammals, he tells us, is to complete 

 the table of classification given by Cuvier in 1800 (in the ' Lemons d' Anatomic 

 Comparee') by extending the same methods of analysis and presentation to 

 the genera. As in Brisson's scheme, a series of dichotomous branchings by 

 means of brackets is arranged under each order. In the section on les 

 "Pedimanes on Marsupiaux" the genera "Sarigue," "Peramele," "Dasy- 

 ure," "Wombat," "Coescoes," and "Phalanger" appear. "Le Kangaroo" 

 furnishes the transition to "les Rongeurs" and appears at the head of that 

 order. 



In short, Dumeril's work shows that more fundamental principles of 

 classification were being discovered; but his classification is essentially 

 Cuvierian, first, in not recognizing the subclass rank of the ]Marsupials and 

 their entire independence from the Rodents and Carnivores and, secondly, 

 in endeavoring to fintl a natural sequence of genera leading from order to 

 order. 



ILLIGER, 1811. 

 'Prodromus ]Mammalium et Avium.' 



The work cited above farther illustrates the great increase in the content 

 of mammalogy during the half century that had elapsed since the tenth 

 edition of the ' Systema Naturae.' Illiger, in contrast with most other natur- 

 alists of that time, attempted to cover only a limited territory (mammals 

 and birds in contrast with the Animal Kingdom) in a concise and thorough 

 manner, — an indication of increasing s])ecialization, due to rapidly extend- 

 ing knowledge. The work contains careful generic definitions, an extensive 

 glossary of technical terms, an etymology of generic terms and other com- 

 mendable lexicographical features and was highly praised by lUiger's 

 contemporaries {cf. I^atreille, 1825, p. 2). 



