1894.] MICROvSCOPICAL JOURNAL. 51 



Radiolarian Shale from Manitoba. 



By FRED'K R. carter, 

 montclair, n..t. 



in the American Monthly Micro.scopical Journal for 

 April, 1893, there was a description of some Radiolaria 

 from a locality in Manitoba, and what made the article 

 most interesting to the student of the Radiolaria was 

 the fact that of the 16 species there mentioned 13 were 

 new, and the other 3 were not found in the Barbadoes 

 earth, at least they have not been found as yet. And as 

 specimens of this shale, according to the writer of the 

 article were found to contain large numbers of well- 

 preserved Radiolaria the presumption is that many more 

 species in the 3Ianitoba material will be found to differ 

 from those in Barbadoes. The material therefore is 

 worthy of the closest study, especially as it comes from 

 our own continent. A few words as to the best method 

 of cleaning it may not be amiss now that some of the 

 material is at hand. 



At first sight, it seems very unpromising, especially to 

 one who has become accustomed to deal with the Barba- 

 does earth. For in the first place it is very dark in 

 color as compared with the latter and in addition it is 

 much harder, breaking like a piece of slate. Yon can rub 

 off' some of the material of the Barbadoes earth between 

 your fingers, in fact you can hardly handle it without 

 finding the fingers covered with a white dust ; but this 

 shale is smooth and no amount of rubbing will free any 

 of it. But in reality it is by no means as bad as it looks 

 and can be reduced without much difficulty by means of 

 the ordinary carbonate of soda. The amount of soda 

 used, however, should be greater than in the case of the 

 Barbadoes earth, two or three times as much soda in 

 size as the material to be reduced. Take a porcelain or 

 stone lined saucepan holding about a quart and let it be 



