Decembbe 4, 1908] 



SCIENCE 



809 



cord.' Experiments which were then in 

 progress have been extended until still more 

 of the details of spinal shock following an- 

 atomical transection of the cord have been 

 duplicated (1) by the method of cerebral 

 anem.ia described in the paper cited, and else- 

 where, and (2) by freezing the spinal cord 

 with a spray of ethyl chloride or by the direct 

 application of liquid air. Freezing the brain 

 as a means of stopping the reflexes was prob- 

 ably first done by Professor D. J. Lingle (un- 

 published experiment on frog). Practically 

 all of the effects observed after anatomical 

 rupture of the conduction pathways may be 

 observed when either of the other methods is 

 employed, if the time limits be kept the same 

 when comparing the results of the different 

 methods. We called attention in a previous 

 paper to the fact that strychnine spasms might 

 appear immediately after the beginning of 

 cerebral anemia, or at any time during which 

 the reflexes of the skeletal muscles are absent. 

 I have since shown that, in a curarized ani- 

 mal, strychnine does not cause the return of 

 vaso-motor reflexes in " shock " sooner than 

 they would appear under the usual conditions 

 of the experiment. 



The evidence for my views, drawn as it is 

 from a laborious study of the phylogenetic 

 development of the function as well as the 

 structure of the central nervous system, can 

 not be presented here. Nor is this the place 

 to develop my hypothesis of the return of the 

 reflexes after interruption of the long path- 

 ways, which depends upon facts of the same 

 nature. Both hypotheses will be developed in 

 detail in later papers. It will be sufficient to 

 point out here that, in my opinion, the real 

 problem is to explain the return of the reflexes 

 after injury to the brain or spinal cord, and 

 that a simple solution to both problems lies in 

 the application of the general principles of 

 organic evolution to function as well as to 

 structure. 



F. H. Pike 



Hull Phtsiological Laboeatoey, 

 The Univeesitt of Chicago, 

 November 10, 1908 



' Pike, Guthrie and Stewart, American Journal 

 of Physiology, 1908, XXI., p. 359. See, also, 



A NEW SPECIES OF THE GENUS MOROPUS 



Since the fall of the year 1904 the Carnegie 

 Museum has carried on extensive excavations 

 in a quarry near the Agate Spring Stock 

 Farm on the Niobrara Eiver in Sioux County, 

 Nebraska. The work has resulted, among 

 other things, in the recovery of an almost 

 perfect skeleton of an adult specimen of 

 Moropus elaius Marsh, which will shortly be 

 mounted and exhibited, and upon which the 

 writer intends in the early winter to publish 

 a memoir giving a full account of the osteol- 

 ogy of this great mammal. Among the ma- 

 terial collected are a number of bones repre- 

 senting the remains of another species of the 

 same genus to which, in honor of my esteemed 

 colleague, Mr. O. A. Peterson, I propose to 

 apply the name Moropus petersoni. A more 

 detailed description, accompanied by figures 

 and plates, will be published in the forthcom- 

 ing Memoir. For the present I content my- 

 self with the publication of a brief diagnosis 

 wherein are pointed out some of the differences 

 which distinguished this species and permit 

 of its separation from Moropus elatus Marsh. 



Moropus petersoni, sp. nov. 

 Adult. Considerably smaller in size than 

 Moropus elatus. The dentition, so far as as- 

 certained, does not materially differ from that 

 of the larger species. The top of the cranium 

 is not, however, characterized by a sagittal 

 crest as is the case in Moropus elaius. In 

 order to understand the difference between 

 the two species the accompanying somewhat 

 diagrammatic figure, representing the posterior 

 portion of the top of the skull of the two 

 species, is given. It will be seen that the 

 narrow elevated ridges marked aa do not con- 

 verge on the median line in Moropus petersoni 

 as they converge upon the skull of Moropus 

 elatus. It will further be observed that the 

 interparietal bone ip in Moropus petersoni is 

 quadrate in form, whereas in Moropus elatus 

 it is subtriangular in form. The cervicals in 

 Moropus petersoni are less massive; the fore 

 limbs are proportionately slenderer; the 

 scapula is relatively longer and narrower than 

 Rosenthal and Mendelssohn, Neurologisches Oen- 

 tralUatt, 1897, XVI., 978. 



