FORAMINIFERA 



401 



Bj% a ^" 



k J 1 



d ...;;: 



# @ 



Fig. 187. Diagram illustrating the life-cycle of Peneroj)lis pertusus 

 (Winter), a-f, megalospheric generation; g, gamete formation; h-k, 

 isogamy; 1-n, microspheric generation; o, multiple division. 



Genus Keramosphaera Brady 



Test calcareous, perforate 



Test vitreous with a glassy lustre, aperture typically radiate, not 

 trochoid 

 Test planispirally coiled or becoming straight, or single-chambered; 

 fossil and recent Family 24 Lagenidae 



