OF THE PROTOZOA. EHTZOPODA. 217 



elements of Gregarince, viz. to the Navicelke developed from the contents 

 of those animals, and to the brood of germs developed out of the contents of 

 an encysted Vorticella : and it may so happen with the Foraminifera, that 

 their entire substance is resolved into germs ; indeed, a progressive formation 

 of such germs is intimated by the circumstance of the ultimate chamber being 

 the last to become completely emptied. 



Although, therefore, the figure and size, the peculiar and successive empty- 

 ing and distribution, the evident periodical appearance in the spring, and the 

 analogy of other Protozoa speak for the hyjDothesis of these globules being 

 reproductive germs, it must, on the other hand, not be concealed that their 

 peculiar composition out of granules imperfectly bound together and enclosed 

 by a membrane, and their remarkable resistance to the strongest acids and 

 alkalies, are facts opposed to this supposition. Hoping to elucidate theii- 

 purpose, Schultze, in some few cases, isolated those shells filled ^dth these 

 black balls, but, after keeping them several weeks, could discover no change 

 in them. 



Ehi-enberg siu-mised that the Polytlicdamia propagated by ova, and thought 

 he perceived in them a sexual apparatus. On the surface of the shells of 

 some samples of Geojoonus {Polystomellci) and Nonionina, from Cuxhaven and 

 Christiania, he discovered stalked, yeUow, membranous sacs, which he repre- 

 sented to be ova-sacs. When first thrown out they were soft and small, but 

 soon swelled up and hardened in the water. Schultze also met with many 

 specimens of Geoponus, at Cuxhaven, having Cothurnice afiixed to their shells, 

 and of a yellow colour, which he believes Ehrenberg mistook for ova- cases. 



Being so unsuccessful by direct observation in his attempts to detect the 

 method of reproduction among Foraminifera, Schultze endeavoured by an ex- 

 amination of these beings in their earliest recognized form to gather some 

 knowledge of it. The smallest and youngest beings he met with belonged to 

 the families Rotalid(B and Miliolida}. Those of the latter family have a non- 

 porous shell, and a spherical figure exhibiting the commencement of the spii^al 

 winding which eventually extends to several turns (XXI. 20 a, h). The sheU- 

 contents are quite coloiu'less, and present few granules. As the spiral winding 

 advances, the contents of the first-formed orbicular cell acquire a darker colour 

 from the appearance of fat-drops and sharply- defined proteine corpuscles ; and 

 the sheU simultaneously assumes the characteristic yellow colour. The differ- 

 ence in size of the primary cell in different species is remarkable. Still younger 

 forms of Eotalidce occurred to him, 0*01 of a line in diameter, spherical, and 

 colouiiess, with a delicate glass-Eke calcareous sheU, through the fine open- 

 ings of which fibres protruded. Others also, entii^ely colourless, had a second 

 chamber superposed on the first, or even three or four ; but in the latter 

 instances the characteristic yellow hue made its appearance, and raj^dly in- 

 creased on fiu-ther growth (XXI. 31). A striking variety was, moreover, 

 remarked in the size of the first chamber, even in the same species ; the 

 dimensions of the second and third cells were determined by those of the 

 first. This great variation in size considerably lessens the possibility of the 

 certain specific detennination of young specimens. 



From these researches it follows, that in MilioUdce and Eotalidce, and pro- 

 bably in all other Pohjtlialamia, the first appearance of the animal is in the 

 form of a colourless spherical mass, invested by a delicate calcareous waU, — 

 the mass consisting of a homogeneous, sparingly-granular Amoeha-hodcy . This 

 first-formed cell has the faculty of producing others like itself from those 

 portions of its sarcode substance. 



Of the manner in which successive chambers are formed, we learn from 

 Dr. Carpenter that the addition of new zones (in the Pohjtlialamia) probably 



