378 The American Geologist. June, 1900 
later he stated that the Dictyonema was D. sociale Salt., of the Lingula 
flags of Britain. 
In 1874 Prof. G. Dewalque stated that the slates of Fumay were 
identical with those of Llanberis (Wales) and that the Belgian sys- 
tem Revinien corresponds exactly to the Lingula flags; also that the 
Salmien could be referred to the Tremadoc shales. Prof. Dewalque 
stated that he had found Eophyton linnseanum Torell, in the Revinien 
of the Ardenne, and a little later that he had discovered in the same 
beds, Protospongia fenestrata Salt., tracks left by Hymenocaris ver- 
micauda Salt., and an Agnostus, fossils characteristic of the Lingula 
flags. In the Devillean he found Oldhamia radiata Forbes, and a 
Primitia. 
The observations of Mr. C. Malaise imply a wider range for Old- 
hamia radiata than the first observers knew of. He found it in the 
Revinien near Rochelinval, and markings like it in the Salmien near 
Spa. 
In 1894 Mr. Hy. Forir noted the presence of a Theca [Hyolithes] 
resembling T. arata Salt., a fossil of the Lower Tremadoc, and recog- 
nized the D. sociale Salt., as identical with D. flabelliforme Eichw. 
From, the above summary of the known (or characteristic) fossils 
of the Belgian Cambrian rocks it would appear that the horizon of 
Dictyonema flabelliforme is definitely established as occurring in the 
base of the Salmien system. There also appears every reason to sup- 
pose that the Revinien represents (in part at least) the Lingula flags. 
There seems less certainty about the exact age of the Devillien. 
If Oldhamia radiata has the w'de range claimed by Malaise it will 
have less determinative value than has been supposed by other geol- 
ogists, and this "system" may represent any part of the Cambrian 
from the Lower Lingula flags downward; its massive w-hite quartzytes, 
however, are likely to prove to be the base of the Cambrian terrane 
in that country as claimed by Andre Dumont. 
From the authors' sections it would seem that the structure of the 
Belgian Cambrian is very complicated and the rocks appear to have 
suffered considerable metamorphic changes, as ottrelite and specular 
iron have been developed in the upper slates of the Salmien. 
Messrs. Lohest and Forir's miemoir is illustrated by a number of 
maps and sections in the text; and by two plates at the end, showing 
the aspect of the surface in worn exposures of the Devillien quartzytes. 
The work is a valuable addition to Cambrian geology. G. F. m. 
Fauna of the Chonopectus Sandstone at Burlingto7t, Iowa. By 
Stuart Weller. (Trans. St. Louis Acad.Sci., Vol. X, pp. 57-130. 1900. 
The second installment of the "Kinderhook Faunal Studies" is for 
several reasons especially welcome at this time. In the first place it 
deal^v/ith the fossils of one of the "yellow sandstones" of Burlington. 
Iowa, about the faunal relations of which there has always been so 
much uncertainty. To all except a few persons who have actually 
collected from these sandstones the fauna of the "yellow sandstone" 
has been almost mythical. Ever since the species were described, 
