Geology. 93 



15. TJie Conard Fissure, a Pleistocene Bone Deposit in North- 

 ern Arkansas, with descriptions of two new genera and twenty 

 new species of Mammals ; by Barnum Brown. Memoirs Amer. 

 Mus. Nat. Hist., Vol. ix, Part iv, pp. 155-208 ; pis. xiv-xxv. — Mr. 

 Brown has made a most notable contribution to our knowledge of 

 North American Pleistocene forms, not alone by this excellent 

 work, but by the rare skill with which he explored and collected 

 the material upon which the volume is based. The assemblage of 

 animals contains thirty-seven genera and fifty-one species, of 

 which four genera and twenty-one species are considered extinct. 

 There is a notable absence of ground sloths, tapirs and proboscid- 

 ians ; the fauna being characterized by northern forms, such as 

 the musk ox and wapiti deer, among others. The condition 

 of the bones, association and predominance of certain forms 

 indicate that this fissure was the home of several contempora- 

 neous species which preyed on others and brought their remains 

 into it, the fauna being typically that of a forest region with open 

 glades similar to present conditions. r. s. l. 



18. A Four-homed .Pelycosaurian from the Permian of Texas; 

 by W. D. Matthew. Bull. Amer. Mus. Nat. History, Vol. xxiv, 

 Art. xi, pp. 183-185. — This remarkable genus, Tetraceratops, is 

 based upon the partially complete skull of a highly specialized, 

 predaceous type. It is characterized mainly by the development 

 of horn-like prominences — one in advance of each orbit and one 

 arising from each of the premaxillaries. Among reptiles the 

 nearest approach to them is seen in the carnivorous dinosaurs 

 Ceratosaurus and Allosaurus, in both of which bony horns are 

 found upon the prefrontals while the first-named genus bears a 

 median nasal horn as well. The horns are more highly developed 

 however, in Tetraceratops. Dr. Matthew's choice of name may 

 lead to confusion, as the group of great horned Dinosauria, the 

 Ceratopsia, includes the genera Ceratops, Diceratops and Tricera- 

 tops, and the unrelated Tetraceratops should logically belong to 

 the same group, if one were to judge from the name. r. s. l. 



11. Osteology of Blastomeryx and Phylogeny of the American 

 Cervidce ; by W. D. Matthew. Bull. Amer. Mus. Nat. Hist., 

 Vol. xxiv, Art. xxvii, pp. 535-562. — The lower Miocene fauna has 

 supplied the connecting link between the Oligocene Leptomeryx 

 and the later American deer in the form of Blastomeryx, the 

 osteology of which is completely known. This enables Dr. 

 Matthew to trace the evolution and relationships of the American 

 Cervidse in a way which places the phylum on a plane with those 

 of the Horses and Camels. Figure 14 is a diagram showing the 

 evolution and migration into South America of the North 

 American deer, while fig. 15 gives us a most valuable summary 

 of the geological distribution and phylogeny of the American 

 ruminants as a whole. r. s. l. 



18. Rhinoceroses from the Oligocene and Miocene deposits of 

 North Dakota and Montana; by Earl Douglass. Ann. Car- 

 negie Museum, Vol. iv, Nos. iii and iv, 256-266, pis. lxiii, lxiv. — 



