rJIIZOPODA. 



29 



the possession of an outer case or shell, and for a long time they were 

 known to naturalists by their sliells alone. As the shell or test is 

 usually very beautifviland often very complex, the Furaminifera were 

 consequently placed at first amongst the true shell-fish {Mollvsca), 

 very much in advance of their true position. When, however, the 

 anatomical structure of the group came to be investigated, it was 

 soon found that they were really referable to the Protazoa, and that 



Fig. S. — Forainiiiifera. a The animal ('>f Konloiuna, after tlie .slrt'U has be^n venioved 

 by a Avpak acid ; & ^.'rn'm Vt (after Wcliilltze), stiowiiig the shrll surrounded hy a net- 

 work of filaments derived from the hodv-sulistance. 



in point of fact they even occujiy a low positiiui in tlii.s .sub-kingdom. 

 However elaboiate and complicated tlie shell may lie, tlie body of 

 the contained animal is composed sim|ily of granular gelatinous sar- 

 code, highly elastic and contractile, and usually reddish or yellowish 

 in colour (fig. 8, '()• This sareode not oidy fills the shell, but also 

 in many cases gains the exterior by means of little jiei'foi-ations in 

 its walls, and forms a thin film over its ciutei' suiface. Wherever 



