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PRINCIPLES OF EMBRYOLOGY 



Figure 8.i 

 Generalised diagram of insect embryonic development : (a) is a section show- 

 ing the cleavage nuclei, which collect at the surface to produce a blastoderm 

 [b). The number of cells increases, and two densely aggregated groups appear 

 (c). These come together and fuse to form a single germ-band (d). Figures 



