Fossils of the Calciferous Sandrock, 345 



hourly amount by means of a very simple apparatus, moved by 

 an ordinary clock at the rate of 1 inch per hour. The ozone-test 

 thus constructed consists of strips ot calico, about an inch wide, 

 moving over a slit in a closed box, so that the time of the greatest 

 amount is thus indicated, and may be compared with advantage 

 with the diurnal changes in the atmosphere, as indicated by the 

 barometer's oscillations, temperature, moisture, and the direction 

 and changes of the wind ; and I am led to believe that this me- 

 thod is the only one which will ever give decided results, by thus 

 making time an element of the observations. 



[To be continued.] 



ART. XXVII. — Fossils of the Calciferous Sandrock, including 

 those of a deposit of white limestone at Mingan, supposed to 

 belong to the formation. By E. Billings. 



(Extracted from the Report of the Geological Survey of Canada for 



1858-1859.) 



The following paper contains notices of all the species of organic 

 remains that have been collected in Canada up to the present 

 date from the Calciferous Sandrock, including a deposit of white 

 limestone, supposed to belong to the formation. This white 

 limestone has been observed only at the Mingan Islands, where it 

 overlies the Calciferous Sandrock, and is in its turn overlaid by 

 the Chazy. Twelve species have been collected in this rock, and 

 of these, only three occur in the true Calciferous Sandrock, but 

 none of them have yet been found in the Chazy. 



Of the forty-one species noticed in this paper, none have been 

 clearly identified with those of the Chazy or any more recent for- 

 mation, although several of them, such as Eunema prisca, Pleu- 

 rotomaria calcifera and P. Laurentina are closely allied to 

 species of the Black River limestone. It is not certain that the 

 siphuncles I have referred to Orthoceras multicameratum, belono- 

 to that species. Future discoveries may possibly prove to the 

 contrary, but, according to our present knowledge, the fauna of 

 the Calciferous Sandrock in Canada is almost entirely distinct 

 specifically from that of the Chazy. 



