180 



SCIENCE. 



[N, S. Vol. XIV. No. 344. 



Dr. Omori has compared the time of the ar- 

 rival of the beginning of three of the phases 

 mentioned above, namely the first preliminary 

 tremor, the second preliminary tremor, and the 

 quick-period phase of the principal poi^tion, 

 and he has assumed, as he is quite justified in 

 doing, that they originated simultaneously at 

 the seismic origin. He has compared the ve- 

 locities of transmission of these three phases 

 between Italy and Japan, in ten earthquakes, 

 with results which agree among themselves in 

 the most remarkable way. 



The means are, for the first preliminary, 12.8 

 km. per second ; the second p)r el iminary, 7.2 km. 

 per second, and for quick i^eriod of the principal 

 portion 3.3 km. per second. The latter quan- 

 tity, it will be observed, is what is usually 

 thought of in speaking of the velocity of an 

 earthquake wave. 



Now no known rock has a modulus of elas- 

 ticity high enough to transmit a wave, of either 

 compression or distortion, with the speed of the 

 first preliminary tremor as shown above, and it 

 seems impossible to avoid the conclusion that 

 this disturbance must be transmitted along 

 some shorter path within the earth's crust, 

 while the principal portion undoubtedly travels 

 along the earth's surface. This question is 

 greatly complicated, however, by the fact that 

 the duration of the first preliminary at a given 

 observation station is very nearly simply pro- 

 portional to the surface distance from the origin 

 of the disturbance. 



It is impossible to close even so brief a notice 

 as this must be, without again congratulating 

 Dr. Omori and his colleagues of the Earthquake 

 Commission upon the splendid way in which 

 they are making use of the rare opportunities 

 which they enjoy for seismological study. The 

 indirect results of this study, especially as they 

 are related to the general subject of terrestrial 

 physics, promise to be of the greatest impor- 

 tance, and the Japanese seismologists may well 

 feel assured that they are practically in control 

 of a field worthy of their highest efforts. 



The general form and style of these publica- 

 tions is so excellent that it may be worth while 

 to call attention to the existence of a few blem- 

 ishes, doubtless due to careless proof-reading. 

 One is tempted to especially mention one of 



these, which is the frequent" appearance of 

 Alasca or Alascan, in which form alone, indeed, 

 is found the name of the territory, or whatever 

 it may really be, known to us who own it as 

 Alaska. 



T. C. Mendenhall. 



Beitrag zur Systematik und Genealogie der Rep- 

 tilien. Bj^ Max Furbringer. Abdruck aus 

 6er Jenaische Zeilschrift fiir Naturwissenschaft, 

 XXXIX. Bd. (N. F. XXVII.). Jena, Verlag 

 von Gustav Fischer. 1900. Pp. 1-91. 

 The paper to which the attention of all who 

 are interested in the class of reptiles is here 

 called is only a portion of an extensive memoir, 

 a summing up of the results of studies detailed 

 in the twenty-seventh volume of the Jenaische 

 Zeitschrift and occupying over four hundred 

 pages of that journal. In view of the author's 

 important contributions to zoological literature, 

 especially of his great work on the morphology 

 of birds, anything that he may have to say on 

 the kindred group of reptiles must attract at- 

 tention. 



The author first discusses the position of the 

 most primitive Reptilia and the origin of the 

 Sauropsida (I.) ; then a survey is made of the 

 systematic and genealogical relationships of the 

 various orders (II.) ; and finally, these are 

 grouped into subclasses, and their genealogical 

 relation to the other Tetrapoda is treated (III.). 

 I. Of the living reptiles the Lacertilia and the 

 Rhynchocephalia are regarded as the most 

 primitive ; of the latter a single representative 

 exists ; of the Lacertilia about 1,600. Contrary 

 to what is generally held, the author does not 

 regard Sphenodon as the most primitive reptile, 

 although it possesses many primitive features. 

 A just appraisement of all its characters places 

 it lower than the highest Lacertilia, but higher 

 than the lowest representatives of the latter. 

 The author contends that in the primitive 

 reptiles the quadrate bone was movable (strep- 

 tostylic), and that its fixed (monomostylic) con- 

 dition is the result of secondary modifications. 

 Some of the earlier Rhynchocephalia, as Pat- 

 teohatteria, were probably the lowest of known 

 reptiles. Notwithstanding their differences, 

 the Lacertilia and the Rhynchocephalia had a 

 common ancestor. 



