CLASSIFICATION 57 



examination of the rich collections dredged hy the 

 ' Challenger ; ' and the removal of the Textularida 

 and the Buliminida to a separate family, the Textu- 

 LARHDiE. The retention of this latter group would 

 seem to throw douht on the utility of regarding differ- 

 ences of shell structure as a canon of classification, 

 since this family contains examples of both types of 

 structure, the arenaceous and the hyaline. There is 

 also another weakness in the arrangement, which has 

 been lately emphasised by Continental systematists, 

 as Eimer and Fickert, and was also remarked upon 

 by Brady himself — namely, the presence, in the familj^ 

 of the LiTuoLiD.E, of numerous arenaceous isomorphs 

 of the hyaline forms. 



But, with the exception of these perhaps unavoid- 

 able discrepancies, Brady's classification has the 

 merit of being quickly and easily understood by the 

 student of Foraminifera, and it certainly holds the 

 field in point of the number of writers who still make 

 use of it. 



It will be useful, however, to insert at this place 

 three of the latest classifications of Foraminifera. 



Dr. Biitschli (1880) divides the Rhizopoda, as did 

 Max Schultze, into two sub-orders, Amoehcca (Nuda, 

 Schultze) and Testaceci. 



Testacea, M. Schultze. (TJialamojyJwra, R. Hertwig.) 



A. Tribe. — Imperforata, Carpenter. 



Family 1. Arcellina, Ehrenberg. 

 ,, 2. Euglypliina, Biitschli. 



