340 



E. R. HOSKINS 



cells, whereas in the wall of the gland between the tubules there 

 are three or four layers. Here, as in all the other stages, the 

 peripheral, actively growing, and therefore young cells are round 

 or nearly so, and contain large round nuclei and relatively little 



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Figs. 7 and 8 X 100. Transverse sections through the middle of the digiti- 

 form gland of Acanthias embryos, showing tubule formation and cytomorphosis. 



Fig. 7 Embryo 28.1 nun. in length. 



Fig. 8. Embryo 95 nun. in length. 



Only four orders of tubules are shown in figure 8, although in some parts of 

 the gland in this stage six orders of tubules may be found (see fig. 6). 



