54 The American Geologist. .Fanuary. 1901. 
hornblende. (3) normal hornfels containing "augen" and green horn- 
blende; and two from the upper contact: (4, 5) hornfels and arkose 
hornfels containing richly scattered crystals of andalusite. Each type 
is described in detail ; and the evidence is shown to strongly support 
the intrusive origin of the diabase, the andalusite and the fact that the 
hornstone a hundred feet above the upper contact is baked as hard as 
any below the sheet, being especially conclusive in this regard. Another 
contact tj'pe is believed to be a leucite hornfels, although the analysis 
shows it to be too high in alumina and soda and much too low in potash 
for a pure leucite ; the discrepancy being attributed to interstitial mat- 
ter. Leucite has not been previouslj' described as a contact mineral. 
w. 0. c. 
Uebcr grossc Haclic U cberschiebungen in Dillgcbiet, von Herrn E. Kay- 
SER in Marburg in Hessen. (Jahrbuch de Konigl preuss, geologi- 
schen Landesanstalt for 1900, Bohn, p. 7.) 
This article describes the complicated structure of the Devonian and 
Culm in the neighborhood of Dill in southern Germany. A complicated 
series of upthrow and downthrow of faults is shown by the accompany- 
ing map, a? cutting all the older formations, but not so much affecting 
the Culm though this formation is also cut by them. Several sections 
are given to show the details of the action of the force that produced 
these movements : and it is also shown that after the faults were pro- 
duced a continuation of the movement caused the folding of the bed 
affected by the fault — (page 8). 
Uebcr den nassauisclicii Cului, von E. K.wser (Neues Jahrbuch fiir 
Mineralogie etc., 1900, Bd. I, p. 132). 
In this paper Prof. Kayser refers to the discovery by Tornqvist in 
the Posidononia slate of Hebron of a species of Meek's North Amer- 
ican genus Euchondria (E. curopaea Tornq.) of which he himself had 
found a verj- perfect example. G. F. m. 
Beitragc cur Kcnntniss des Sibcrischcn Cambriuin, I. von Eduard vox 
Toll. (Memoires de I'Acad. Imp. des Sciences de St. Petersburg, 
viii Ser., vol. viii. No. 10. 
This quarto of 57 pages with a number of cuts in the text and eight 
plates of figures of the fossils described, is one of the most important 
contributions to Cambrian literature that have appeared in the last few 
j'ears: not only on account of the thorough treatment of the subject, 
but also because of the distant and little known geological field whose 
Cambrian fossils are described herein. 
Both on the Yenesei, and the Lena the great rivers of Siberia, Cam- 
brian deposits are now known to exist, and they supply most interesting 
links of association with the contemporary strata on the opposite side of 
the world. 
Very noticeable is the fulness with which the archa^ocyathine reef 
builders were multiplied in the valley of the Jenesei, and their numerous 
species have to a large extent been identified by Baron Toll with Born- 
eniann'^; species in Sardinia. 
