532 



SCIENCE. 



[N. S. Vol. XIV. No. 353. 



the ilium ; the fact that the posterior sacral is 

 larger than the anterior, showing the enormous 

 power exerted by the tail ; the coossification of 

 the 17th and 18th caudal vertebrae, indicating 

 that this was a fixed point when the animal 

 stood upon its hind feet and partly supported 

 itself upon the tail in the tripodal condition ; 

 the excessively small neural canal throughout, 

 the probable presence of a pair of clavicles, not 

 hitherto observed in the Sauropoda ; the hollow 

 character of the large limb bones. 



These skeletons are referred to a new species, 

 D. carnegiei, in honor of the founder of the 

 Pittsburgh Museum. 



As regards the habits of these animals Mr. 

 Hatcher speaks as follows : 



From the above consideration I am inclined toward 

 the opinion that Diplodocus was essentially an 

 aquatic animal, but quite capable of locomotion on 

 land. Though living for the most part in the more 

 important rivers and fresh-water lakes, it may not 

 infrequently have left the water and taken temporar- 

 ily to the land, either in quest of food or in migration 

 from one to another of adjacent bodies of water. 



It is not improbable that during the period when 

 these huge dinosaurs lived and flourished over what is 

 now New Mexico, Colorado, Wyoming, Montana and 

 the Dakotas, there prevailed throughout this region 

 physical conditions somewhat similar to those which 

 exist to-day in tropical America and more especially 

 over the costal plain of the lower Amazon with its 

 numerous bayous and islands, or the more elevated 

 valleys of the anterior in the Brazilian provinces of 

 Amazonas and' Matto Grosso with their numerous 

 lakes and large rivers surrounded by a dense tropical 

 vegetation with broad, level valleys subject to period- 

 ical inundations. 



With the beginning of the Cretaceous there began a 

 subsidence over this region, and a great inland sea 

 was formed which gradually encroached upon the 

 habitat of these animals, more and more restricting 

 the area adapted to them, so that at about the com- 

 mencement of the Upper Cretaceous the entire region 

 formerly occupied by them had become a shallow sea 

 save only certain islands of limited extent, and per- 

 haps otherwise poorly adapted as the homes of such 

 animals as were the Sauropoda. 



A few years more of such efficient exploration 

 as this and of such remarkably careful field and 

 preparation work promises to give us a knowl- 

 edge of the osteology of these great Sauropods 

 almost as complete as our knowledge of the 



skeleton of the recent horse, for example. The 

 author of the present work and Dr. J. L. 

 Wortman, who found the type skeleton, have 

 led the way in these methods of field work. 

 Henry F. Osborn. 



An Introduction to Physiology. By William^' 

 TowNSEND Porter, M.D., Associate Professor 

 of Physiology in the Harvard Medical School. 

 Cambridge, Mass., The University Press. 

 Pp. 314. 



This small volume contains in a convenient 

 form what is apparently the course of practical 

 physiology given for the past two or three years 

 at the Harvard Medical School. To those who 

 are not conversant with the difficulties that be- 

 set the practical teaching of the subject to large 

 classes it may appear surprising that in this mat- 

 ter the large American medical schools should 

 have lagged behind the smaller, in some of which 

 courses of a considerably wider scope than that 

 under review have not only, for the best part of 

 a decade, been available for the advanced stu- 

 dent of medicine, but have taken their place 

 among the compulsory subjects of the ordinary 

 curriculum. He, however, who knows how 

 much wise planning and laborious organization 

 —what material, intellectual and even moral 

 resources — are required for the successful con- 

 duct of a practical class for a couple of hundred 

 students will be much more ready to congratu- 

 late Dr. Porter and the Harvard Medical School 

 on the satisfactory results of their efforts than ■ 

 to criticise them as belated laborers in the vine- 

 yard of practical physiology. Nor will the ex- 

 perienced teacher whose circumstances enable 

 him to make free use of mammals as well as 

 frogs seriously blame, however much he may 

 regret, the entire omission of mammalian exper- 

 iments, except those performed on the students 

 themselves. He will nevertheless note that the 

 lack of this element, so valuable, under proper 

 conditions, in the training of the medical stu- 

 dents, renders the book less suited to the re- 

 quirements of schools of moderate size than 

 would otherwise be the case. On the other hand, 

 for those who are so situated that they can 

 only use frogs, the work may be recommended 

 as a sound guide to the performance of the fun- 

 damental experiments in the general physiology 



