72 Scientific Intelligence. 



of Rontgen's paper, nearly two years since, that it is impossible 

 for many of those now interested in the subject to keep them- 

 selves fully informed as to what other workers have done. Hence 

 this carefully prepared and conveniently arranged bibliography 

 will be found widely useful. It is intended to include references 

 to all important papers that have appeared up to March, 1897. 

 The editor has given in the introduction a brief summary of the 

 historical development of the subject; he also adds a chapter 

 giving suggestions as to the best method of overcoming some of 

 the mechanical difficulties involved. 



12. Tafeln und Tabellen zur Darstellung der Ergebnisse Spec- 

 troskopischer und Spectrophotometrischer Beobachtimgen. Her- 

 ausgegeben von Th. W. Engelmann", Professor in Utrecht. Leip- 

 zig, 1897 (Wm. Engelmann). — This publication includes ten 

 copies of each of two accurate and well executed plates and two 

 sets of tables. The first of the plates gives at the top the solar 

 spectrum with the Fraunhofer lines and in line with this below 

 five copies of the spectrum of white light with scale divisions 

 arranged according to wave length (from 80 to 40). This plate 

 is designed as a foundation to be used in recording the various 

 absorption spectra under examination. The second plate gives 

 at the top the usual colored spectrum with a similar scale, the 

 position of the Fraunhofer lines are also indicated;, below are a 

 system of ruled horizontal lines, the vertical lines corresponding 

 to the wave lengths and the horizontal lines arranged from 100 

 to 0. This plate is intended for use in the photometric measure- 

 ments connected with the observations of absorption spectra ; 

 detailed suggestions are added in regard to the proper method of 

 recording to be employed. 



Of the two tables, the first gives the numerical values of the 

 coefficients of extinction (e) for variations of light intensity (i) 

 from 99-5 to 0*1. The second gives the relative intensities of the 

 light transmitted through layers of thicknesses 1*0 to 0*1, relating 

 to the amount of coloring material present. 



, 



II. Geology and Natural History. 



1. Paleozoic faunas of the Argentine ; Professor E. Kayser 

 of Marburg, in an article entitled " Beitrage zur Kenntniss 

 einiger palaeozoischer Faunen siid-Amerikas," (Zeitschr. d. 

 deutsch. Geol. Ges., 1897,) has brought together a valuable descrip- 

 tion of the paleontological faunas of Argentine accessible to study 

 in Germany. Five separate lots of fossils from different sources 

 and collected by different hands were studied and results reached. 

 These may be summarized as follows: 



I. A Cambrian fauna from Iruya and Ojo de Agua in the 

 province of Salta, Northern Argentina, in a grey, tine-grained 

 quartzite sandstone, contains the following species, viz : Liostracus 

 iSteininanni n. sp., L. Ulrichi n. sp., Agnostus iruyensis n. sp., 

 Orthis saltensis Kays. ?, Lingulella cf. ferruginea Salt., and Lin- 

 gulella cf. Davisii Salt. 



