~r> Scientific Intelligence. 



keepsie region, greatly complicated through folding and thrust 

 faulting, is described in this bulletin. For many years Professor 

 Dwigbt of Vassar College collected the fossils, and among them 

 the 25 to 30 species of nautilids in which Hyatt was so much 

 interested, and of which almost nothing is yet known. 



The basement upon which the sedimentaries are laid is the 

 gneiss of Fishkill mountains, thought to belong in the Grenville 

 series. Upon this lies unconformably the Lower Cambrian or 

 Poughquag quartzite with Olenellus. There is then a long "lost 

 interval," followed by the Barnegate limestone of Upper Cambrian 

 age, and with a fauna in the basal beds like that found near Sara- 

 toga, New York. This series at Rochdale is from ]000 to 1200 

 feet thick, and also has the cephalopod fauna referred to. Another 

 time break, and then follows a thin limestone with Tetradium 

 cellulosum indicative of Lowville time, over which lies the Tren- 

 ton limestone. The great mass of surface exposures is taken up 

 by the "Hudson River slates" of the Atlantic province, which 

 now override the above-mentioned formations of the Mississippian 

 sea. c. s. 



15. Brief Notices of Some Recently Described Minerals. — 

 Neocolemanite is a calcium borate occurring near Lang, Los 

 Angeles county, California, described by A. S. Eakle at the spring 

 meeting of the Geological Society of America, at Berkeley, Cal. 

 It is related to colemanite, but differs somewhat in its crystallo- 

 graphic and optical properties. A preliminary notice says that 

 the deposit consists of alternate layers of crystallized borate and 

 carbonaceous shales and has apparently been formed by the 

 action of boracic acid on a lake or marsh deposit of calc-tufa or 

 marl. The silicoborate of lime, howlite, occurs with the neocole- 

 manite as snow-white, nodular compact masses ; it has been formed 

 at the same time as theneocolemanite by precipitations from solu- 

 tions containing soluble silica. The deposit is remarkable as a 

 pure borate deposit unaccompanied by other calcium minerals or 

 by sodium salts. 



Molengraaffite is described by H. A. Brouwer from the 

 lujaurite of thePiland mountains, northeast of Rustenburg in the 

 Transvaal, South Africa. It occurs in yellowish brown prismatic 

 forms, having a perfect cleavage like that, of astrophyllite, to 

 which it has some relation and the place of which it sometimes 

 takes in the rock. There are also numerous pseudomorpbs of 

 catapleiite after eucolite. Chemically molengraaffite is more or 

 less related to yttrotitanite, but it contains none of the rare 

 earths, while soda is present in large amount. An analysis by 

 Wijdhoek gave the following results : 



Si0 2 Ti0 2 A1 2 3 Fe 2 3 FeO MnO CaO MgO Na 2 K 2 H 2 

 28-90 27-70 375 0-95 2-07 2-72 19-00 2-38 10-30 0'60 1-00=99-37 



— (Jentralblatt fiXr Mineraloc/ie, etc., p. 129, 1911. 



Gajite is a hydrated carbonate of calcium and magnesium 

 described by Fr. Tucan from the Gorski-Kotar district in Upper 



