Januaky 19, 1900.] 



SCIENCE. 



115 



of the International Cloud Work for the United 

 States,' American Journal of Science, Decem- 

 ber, 1899, 433-444. A preliminary statement 

 of results which are soon to be published in ex- 

 tenso by the Weather Bureau. 



Oliver L. Fassig : ' Types of March "Weather 

 in the United States,' American Journal of 

 Science, November, 1899, 319-340. A discus- 

 sion of the relations existing between the mean 

 atmospheric pressure, the prevailing character 

 of the weather and the paths of storms. 



Willis L. Moore : ' Report of the Chief of 

 the Weather Bureau for 1899,' U. S. Depart- 

 ment of Agriculture, Weather Bureau. 8vo. 

 Washington, D. C, 1899. Pp. 23. 



B. S. Pague : ' The Mild Temperature of the 

 Pacific Northwest, and the Influence of the 

 KuroSiwo.' 8vo. Portland, Ore., 1899. Pp. 

 11. Charts III. The author classifies the tem- 

 perature conditions of the north Pacific Coast 

 into continental, dynamic and oceanic types. 

 He believes that dynamic heating of descending 

 air is more eflTective than the influence of the 

 ocean in producing the mild winter tempera- 

 tures of the Pacific Northwest. 



R. Dec. Ward. 



Harvard University. 



RECENT ZOOPALEONTOLOGY. 



Adaptive radiation of the Camels and Llamas. — 

 Professor Scott advances the following hy- 

 pothesis in his recent important memoir : 



"The most interesting and striking result to 

 which the study of the Uinta selenodonts has 

 led is the very unexpected conclusion that, 

 with the possible exception of the oreodonta 

 and agriochoerids, all of the strictly indigenous 

 North American selenodonts are derivatives 

 of the tylopodan stem. Paradoxical as this 

 conclusion may appear, I believe it to be fully 

 justified by the evidence which will be laid 

 before the reader. The Tylopoda are thus seen 

 to be a very ancient and highly diversified 

 group, comparable in this respect to the 

 Pecora, or true ruminants, which they so 

 closely resemble in many features. The Pecora 

 are an Old World group, which underwent 

 great expansion and diversifications in Eurasia, 

 but did not reach this continent till late Mio- 

 cene times, and never attained the importance 



here that they have so long had in the Eastern 

 Hemisphere. Their place was, to a verjf great ex- 

 tent, taken in America by the Tylopoda, which 

 ran a course of development in many ways par- 

 allel to that of the Pecora and Tragulina, but 

 with a variety and diversity of structure, habit,, 

 and appearance, such as are not attained in 

 either of the latter groups." It has long been 

 known that the Canjels and Llamas had their 

 home on this Continent, but Professor Scott'a 

 hypothesis, that practically all the American 

 Artiodactyls, except the pigs, sprang from a 

 common cameloid stem, is of the greatest in- 

 terest. If confirmed, it will take rank as a 

 brilliant generalization resulting from recent 

 exploration. Even if not confirmed, it will be 

 of great value as stimulating closer inquiry into 

 the natural relationships of the American even- 

 toed Ungulates. Trans. Wagner Free Institute^ 

 Phila., May, 1899, Vol. VI. 



The Pliocene Hyrax. — PUohyrax Osborn is 

 identical with Lepiodon Gaudry. This rather 

 dry announcement relates to an interesting ex- 

 tension of our knowledge of the Hyracoidea. 

 For some years a skull found upon the Island 

 of Samos awaited description in the Stuttgart 

 Museum ; Professor Fraas kindly placed it in 

 the hands of Professor Osborn, who described 

 it before the International Zoological Congress, 

 at Cambridge, as a new and very remarkable 

 form of Hyrax from the Lower Pliocene, as the 

 only fossil representative of this order and as be- 

 longing to a distinct family of Pliohyracidae and 

 a distinct genus PUohyrax kriipii It now appears 

 that the lower jaw found by Professor Gaudry in 

 Pikermi, Greece, and long known as Leptodon 

 graecus belongs to the same type as the above. 

 Dr. Max Schlosser, of Munich, points this out 

 in an interesting article in the Zoologischen An- 

 zeiger of October. He leaves the animal among: 

 the Hyracoids and suggests that it is of South 

 American origin, a suggestion of considerable 

 probability and of very great interest. 



Exploration for Dinosaurs. — Great activity 

 prevailed last season in the search for the re- 

 mains of Dinosaurs. A report of the parties 

 exploring in the Dinosaur beds under the direc- 

 tion of Professor W. C. Knight has already 

 been made in this Journal. In addition to 



