68 THE FORAMINIFERA 



short time the coarse brown granules, hitherto contained within 

 the test, begin to pass out, and ultimately the whole of the proto- 

 plasm, emerging from the test, is massed within the area covered 

 by the halo and lies between the test and the supporting surface 

 (Fig. 10, b). Here, after involved streaming movements, the proto- 

 plasm gradually and simultaneously separates into spherical masses 

 of uniform size. The centre of each is occupied by a nucleus, with 

 an area of clear protoplasm immediately surrounding it. A close 

 network of delicate pseudopodia surrounds the spheres and forms 

 a communication between them (Fig 10, c). In a short time each 



X ' 





FIG. 10 (conti7iued). 



d, later stage in the reproduction of the specimen of Polystomella crispa represented in Fig. 

 10, a-c. 



sphere secretes a calcareous shell, a single small aperture being left 

 by which the pseudopodia pass out. After lying in close contact 

 for some hours, the spheres rapidly and simultaneously draw apart 

 from one another, and within half an hour from the beginning of 

 the movement they are dispersed over a wide area, and each 

 becomes the centre of a system of pseudopodia of its own, though 

 for some time they are not completely isolated (Fig. 10, d). 



The whole protoplasm of the parent is used up in the formation 

 of the brood of young, the shell being left empty. The process, 

 from the first appearance of the halo to the dispersal of the young, 

 is complete in about twelve hours. 



