330 LEADING AMERICAN MEN OF SCIENCE 



derived from his experience. The proposition that "the ancestors 

 of the hoofed animals possessed bunodont or hillock-like teeth" 

 was originally advanced by him and then was verified by the oppor- 

 tune discovery of Phenacodus. It led to a reclassification by him 

 of the Ungulates by foot structure. To Cope is due the chief credit 

 in establishing the principle "that the primitive feet of hoofed 

 animals were plantigrade, like those of the bear with serial unbro- 

 ken joints," which according to Osborn constituted "the first 

 distinct advance in mammalian classification since Owen demol- 

 ished Cuvier's 'pachydermata.' ' The same authority may be 

 quoted as describing Cope's conclusions as ranking "with Huxley's 

 best work among similar problems, and they afford a basis for the 

 phylogenetic arrangements of the hoofed orders which has been 

 adopted by all American and foreign paleontologists." From his 

 studies of the collections from the Basal Eocene he derived his 

 "Law of Trituberculy," that is, "that all types of molar teeth in 

 mammals originate in modifications of the tritubercular form." 

 This generalization is of the utmost value, for upon it may depend 

 the whole modern morphology of the teeth of the mammalia and 

 the establishment of a series of homologies in the teeth of the most 

 diverse types, applying even to the teeth of man. That "the hoofed 

 orders converge towards the clawed types of Creodonta and Insec- 

 tivora" is a law which he also laid down and demonstrated by a 

 fortunate discovery in the field. He defined the primitive suborder 

 of Carnivora, now universally adopted under his name of Creo- 

 donta; and he added much to our knowledge of the whole order, 

 especially of the true cats. The mechanical origin of the hard 

 parts of the bodies of mammals, especially the teeth, vertebrae, 

 and limbs received his consideration and he published many papers 

 on this subject, which culminated in his memoir on the "Origin 

 of the Hard Parts of the Mammalia" (1889). 



Fitting indeed, as a closing paragraph to these brief summaries 

 of his specialties are the following words written by his friend and 

 admirer, A. Smith Woodward of the British Museum: 



"One great feature of this systematic work, everywhere con- 

 spicuous, is the attempt to define every term, whether specific, 



