Geology and Natural History. 489 



2. Fossils from the Silurian Formations of Tennessee, Indiana 

 and Illinois ; by Aug. F. Foerste. Bull. Denison Univ., April, 

 1909, pp. 61-107, pis. i-iv. — Here are described 74 forms of Silu- 

 rian fossils, most of which are new. Of these 40 derive their 

 specific names from localities or men. Seven new subgeneric 

 names are proposed not one of which is clearly established. Two 

 of these are coral subgenera, Crater ophyllum and Plaiyaxum ; 

 of brachiopods, Stec/er/iy?ichiis } Cliftonia, JSchizonema, and Platy- 

 merella, and the bivalve Newsomella. c. s. 



3. Illinois State Geological Survey. Bulletin No. 9. Paving 

 Prick and Paving Prick Clays of Illinois / by C. W. Rolfe, 

 R. C. Purdy, A. N. Talbot and I. O. Baker. Pp. xiii, 316 ; 

 3 plates and 33 figures. Urbana, 1908 (University of Illinois). — 

 This Bulletin is devoted to a detailed discussion of a subject of 

 much general economic importance. The geology of clays with 

 particular reference to their origin and their distribution in the 

 State is described in the opening chapters by C. W. Rolfe. The 

 chapters following, by R. C. Purdy and A. N. Talbot, present 

 the facts in regard to the properties of high-grade paving brick, 

 the tests used in determining them, and the qualities of the clay 

 demanded. The final chapter by I. O. Baker is devoted to a dis- 

 cussion of the proper construction and care of brick pavements. 



4. Wisconsin Geological and Natural History Survey. E. 

 A. Birge, Director, W. O. Hotchkiss, Economic Geologist. — 

 The Wisconsin Survey has recently issued six geological maps of 

 the Lead and Zinc district, together with a leaflet, serving as a 

 Supplement to Bulletin XIV, by U. S. Grant (noticed in vol. xxi, 

 p. 470). 



5. A new locality of Diamonds in Africa. — The discovery 

 of diamonds in German Southwest Africa in May, 1908, was 

 announced some months since in the public press. An account 

 is now given by H. Lotz of their method of occurrence, while 

 E. Kaiser adds a description of the crystalline form. It appears 

 that the gems occur in a loose material consisting of from 70 to 

 80 per cent of reddish fine sand, and the remainder of fine 

 gravel ; associated with the last named are small finely striated 

 pebbles, chiefly of agate and jasper. The principal locality is at 

 Ltideritzbucht, but extends also along the coast to Angras Juntas, 

 half way to the mouth of the Orange River, a distance of 130 

 kilometers. 



The author expresses the view that the diamond deposits are 

 old coast formations in part rearranged by the wind. They are 

 probably connected with the general flood region of the Orange 

 River, the stones offering many points of resemblance to those 

 obtained on the banks of the Orange and Vaal rivers in the 

 interior. The uniform size of the stones is a matter of interest; 

 the majority range from \ to \ carat, the largest stone weighing 

 2 carats, while stones of \ carat are comparatively frequent. 

 The quality is unusually high. Lotz calculates, from the some- 

 what insufficient data thus far available, that a production of 



