256 



THE CANADIAN NATURALIST. 



[Vol. vii. 



^erg long ago recognized them as forming an important consti- 

 tnent of the English chalk, and supposing them to result from 

 a rearrangement and partial crystallization of the particles of car- 

 bonate of lime, called them " morpholites." The name by which 

 they are now known was applied to them by Prof. Huxley, who 

 found them to be characteristic of many deep sea sediments, 

 where they appear in conjunction with the Amoeba-like Bathy- 

 ■iius. It is still a question in dispute, whether they form an 

 integral part of that organism. Rhahdollths were discovered by 

 Dr. 0. Schmidt in 1872* in the Adriatic Sea, in association with 

 Coccoliths, with which they appear to be closely allied in struc- 

 ture and mode of increase. I do not know that they have 

 -lieretofore been found in the fossil state. 



Pig 2. Various forms of Coccoliths (^a) and Rhabdoliths (h) from 

 "^he Cretaceous of Manitoba. 



In the samples of Cretaceous limestone from Manitoba and 

 Nebraska, both Coccoliths and Rhabdoliths are abundant, and 

 •constitute indeed a considerable proportion of the substance of 

 the rock. The engraving represents a selection of the forms 

 •observed, magnified about 1250 diameters. The Rhabdoliths 

 •agree closely with those figured by Dr. Schmidt, f and pass 



* Ann. and Mag. N. H. 1872. 



f Loc. Cit. PI, xvii. 



