380 



THE MlCROSCOrE. 



iiiinuto size for the most part, and consisting, as we 

 have abeady seen, either of one, two, or more con- 

 nected chambers. A jelly-like mass, or " sarcode," occu- 

 j)ies the chambers and their connecting passages ; and, 

 l^u'otruding itself both from the external aperture of 



Fig. 208. 



I, Section of Faujasina: a a, radiating interseptal canals; h, their internal 

 bifurcations ; c, a transverse branch ; d, tubular wall of the chambers. 2, 

 llosalma ornata, with its iiseudopodia protruded. 



the last chamber, and in many cases from the sometimes 

 numerous perforations in the shell- walls, extends itself not 

 only over the surface of the shell, but also into radiating 

 contractile threads ov pseudopodia, and into gemmule-like 

 masses, which latter become coated over with calcareous 

 matter, and thus form additional segments of the animal.^ 

 ^^ Foraminifera, indeed, are to be compared with the 

 other lowest orders of animals and of plants in the study 

 of their specific relations. In these several low forms of 

 creatures we have comparatively few species, but ex- 

 tremely numerous individuals, with an enormous range of 



(1) Among the more important works on Foramini/era, reference may be 

 made to D'Urbigny's Foramini feres fossiles du BassUi Tertialra de Vlenne 

 (.\utri«he); Schultze, Ueber dcii Orgaiiismus der Polythalamien, 1854; Car- 

 Jtenter's and Williamson's Resc'urhcs on the Foraminifcra, I'hil. 2'rans. 1S56, 

 Also an excellent pai)er by Mr. W. 11. Parker, in the Annals of Nahiral History, 

 April, 1857. Specimens of Foraminifera may be obtained for examination from 

 the shaking of dried Sponges; Imt if required alive tliey nmst be dredged for, or 

 l^icked off the fronds of living seaweeds, over the smface of which they maybe 

 been to move by Llie aid of a lens. 



