124 MICROSCOPICAL OBJECTS FOUND 



adds, " Hence, the geographical distribution of 

 living genera and species offers to us a means of 

 comparison of the highest importance, with a 

 view to the determination of the temperature of 

 the waters in which the fossil species lived, and 

 may lead to very satisfactory results in geology, 

 if we may judge by the fruits of our observations 

 in this respect."* 



These conclusions require to be received with 

 the utmost caution, if the study of the Foramini- 

 fera is to be made of any real use in the attainment 

 of new geological truths. Our knowledge of 

 these singular creatures is as yet much too 

 elementary, for us to come with safety to any very 

 general conclusions. M. D'Orbigny's paper, 

 from which the above is quoted, is an evidence 

 of this. After advancing various arguments to 

 prove that the temperature of the great basin in 

 which the Chalk of Europe was deposited, was 

 analogous to that of the Adriatic at the present 

 time, he adds, " To complete the approximation, 

 it (the Adriatic) exhibits to us the only two 

 living species, the analogues of which are found 

 in the fossil state in the white Chalk, viz. Denta- 



* See iirecetliug Note. i\Ir. Weaver's Abstract, p. 457. 



