25*2 



THE AMERICAN NATURALIST [Vol. XLVII 



height of 14 feet the individual tubercles are of very small 

 size, never attaining a greater diameter than 5 millimeters. The 

 paper closes with a reconstruction of Trachodon mirdbile Cope 

 in two attitudes, bipedal and quadrupedal and a discussion of 

 a ''Theory of Color Pattern" and "Habits of the Trachodonts. " 

 In regard to Trachodon annectans Osborn says : 



If the animals had spent any considerable part of their lives on dry land, 

 even on the sands bordering the streams, the effect of the impact would 

 certainly be observed in the retention of hoofs or ungues, in the coarsen- 

 ing of the palmar epidermis of the manus, because the fore limbs would 

 certainly have been used occasionally, at least, in contact with the earth. 

 There are no hoofs and the epidermal thickenings or pads are very 

 lightly developed. 



The conclusion then seems to be that the animals were largely 



The same author in Part III of the same series gives the 

 attempts to arrive at some definite system of measurements for 

 mammalian skulls with especial reference to the horse, in a 

 paper entitled "Craniometery of the Equida?." The author 

 divides the discussion into (I) Craniometric Systems, 1875- 

 1912; in which is given the results of the labors of Franck, 

 1875; Branco, 1883; Nehring, 1884; Tscherski, 1892; Salensky, 

 1902; Ewart, 1907; Bradley, 1907; and Osborn, 1912, the discus- 

 sions being illustrated by figures and tables. (II) Distinctions 

 betiveen Horses, Asses and Zebras. (Ill) Cytocephaly,the Bend- 

 ing of the Face on the Cranium, the chief conclusions of which are : 

 (1) in young animals the palatal and cranial lines are more 

 nearly in the same plane; (2) in certain animals the deflection 

 increases rapidly with age; (3) a horizontal and upward deflec- 

 tion is generally characteristic of primitive browsing types ; (4) 

 the downward deflection of the face and palate is highly char- 

 acteristic of certain grazing types. (IV) Craniometry and 

 Odontometry in Paleontology. 



In fossil skulls the indices lose value because the slightest degree of 

 crushing or distortion seriously disturbs an index. Nevertheless the 

 indices and ratios should be used wherever obtainable. Since fossil 

 skulls and dental series are rarely complete or perfect, the paleontol- 

 ogist requires an additional series of detailed measurements of parts of 

 the skull not needed by the zoologist. 



Harold J. Cook in Volume 7, Parts 3, 4, and 5, of the Nebraska 

 Geological Survey has given descriptions of a new genus and 



