June 12, 1885.] 



SCIENCE. 



489 



tertiary mammals ; and his results have been 

 confirmed by Cope, Bruce, and others, but by 

 no one with such a wealth of illustration as by 

 Professor Marsh. The latter' s generalizations, 

 however, are somewhat vague, and not al- 

 together novel, and in one case inaccurate. 

 Professor Marsh says, ' All tertiary mammals 

 had small brains.' While such is the general 

 law, it has conspicuous exceptions ; as in the 

 lemur Anaptomorphus, described and figured 



the Dinocerata, and will be read with great 

 interest ; and the two superb folding plates 

 which illustrate this chapter have never been 

 approached in the general accuracy of the sep- 

 arate parts, or in the beauty of drawing. In 

 the figure of Dinoceras, however, the humerus 

 is incorrectly drawn, and we believe that the 

 fore-limb is too much flexed (compare plate 

 28, fig. 2). 



The general conclusions form the least satis- 



by Cope, and in some miocene mammals. Of 

 the latter Professor Marsh's selection is not 

 the best to bring out the facts. Aside from 

 this, Professor Marsh's assemblage of facts is 

 of the utmost importance, and well worthy of 

 careful stud}\ 



Chapters v. -xii. are taken up with full 

 and accurate descriptions of the trunk, neck, 

 and limbs. No point of importance is left in 

 doubt, and we may be said to know the oste- 

 ology of the Dinocerata almost as fully as that 

 of any recent group of mammals. Such com- 

 pleteness of material, and fulness of detail, con- 

 stantly excite the reader's admiration. 



Chapter xiii. deals with the restoration of 



factory section of the work. Lack of space 

 forbids any full analysis of this chapter, but 

 some portions of it demand notice. In the 

 main, the scheme of classification of the ungu- 

 lates here proposed agrees quite closely with 

 that made by Professor Cope {Proc. Amer. 

 phil. soc, 1882, pp. 435-447), though with 

 some manifest improvements. No acknowledg- 

 ment of this agreement is made, however, and 

 the reader would not suppose that Cope had 

 ever written on the subject. When the latter 

 proposed the order Amblypoda, including Cory- 

 phodon and the Dinocerata, Professor Marsh 

 rejected it in these words : " A careful consid- 

 eration of the characters of Coiyphodon, so far 



