published by both his contemporaries, laborers in the same field.* I will 

 not imitate this course in my treatment of Prof. Marsh's writings, but 

 will on the other hand, as in duty bound to the truth, correct my own 

 whenever and wherever I have opportunity, always holdiug to the ouly 

 tenable position, that no statement of scientific fact bears date other than 

 that on which it" was printed and published, no matter to what previous 

 publication it may refer. 



Haviug already gone into the discussion of the affinities of these ani- 

 mals, I run rapidly over the characters assigned by Prof. Marsh to a 

 supposed new order Pinocerea (which he now spells as corrected Dino- 

 cerata . Those from the first to and including the fourth are entirely 

 trivial ; the last, which denies air cavities to the cranium is moreover 

 untrue, as they exist in the squamosal region as I have stated. The fifth 

 is not true of all the genera. The definitions from the seventh to the 

 eleventh are of no weight whatever. As the twelfth, he gives "the very 

 small molar teeth and their vertical replacement." This is precisely the 

 state of things in the proboscidian Dinotherium, a form which Prof. 

 Marsh has overlooked. The 13th and loth, "the small lower jaw," 

 and "absence of hallux" are of no weight if true ; but the lower jaw 

 has marked proboscidian features in the symphysis and teeth, and it is 

 probable that some of the species had a hallux. The 16th, "absence of 

 proboscis" is probably an error, certainly so for two of the genera. I 

 have passed over the (6th) "the presence of large postglenoid processes," 

 and (14th) "the articulation of the astragalus with both navicular and 

 cuboid bones," as of some value. They are, indeed, the only characters 

 of any wide systematic significance adduced by Prof. Marsh, since they 

 point indubitably to the Perissodactyla and are common to all of the 

 Eobasileidm. Nevertheless they form but a slim basis of support for an 

 order of mammals, especially when compared with the uniform testi- 

 mony of proboscidian affinity derived from the structure of the posterior 

 palatal and maxillary regions, the cranial expansions, cervical vertebrae, 

 sacrum, pelvis, hind leg, hind foot scapula, fore leg, fore foot, and the 

 concurrent evidence derived from dorsal and lumbar vertebrae, dentition 

 and proboscis. 



If Prof. Marsh desires to see an equal or greater degree of variation in 

 dentition in an order of mammals, let him compare Equus and Rhinoce- 

 rus among Perissodactyla, or Bos, MoscJius, Hippopotamus and Phaco- 

 climrus in the Artiodactyla ; in the length of the nasal bones, DelpMnus 

 and Squalodon among Getaceo, or Homo, and some of the lemurs ; in the 

 number of toes, Felis and Mustela, Ursus, etc., all members of the same 

 orders . 



I should be glad, on the principle of Demortuis nil nisi bonum, to com- 

 mend our critic's remarks on the relations of this supposed order. But 

 Prof. Marsh's ideas on classification are derived from unusual sources. 

 The absence of incisor teeth no more relates these animals to the Artio- 

 dactyla than it relates the sloth to the same order. The presence of paired 



*See Leidy, Proceedings Academy Natural Sciences, 1872, p. 241, 



