374 



ELIOT R. CLARK 



areas grouped themselves so closely together near the tip of the 

 sprout that they could hardly be recognized individually, until 

 they separated again. The nuclear areas do not maintain the 

 same relative position in a branch, for one may actually move 



Fig. 15 Drawings of lymphatic in the tail of hyla pickeringii larva, to show 

 the relation between the nucleus and the rest of the nuclear area. A was drawn 

 while the embryo was in alcohol, unstained. B shows the same lymphatic, while 

 the embryo was still in alcohol, after staining with hematoxalin. The large black 

 dots represent pigment granules. Oil immersion. 



past another (compare in fig. 16 the relation between nuclei 2 h 

 and l h in stages J, K and L). 



The nuclear areas which have once passed into a branch, do 

 not necessarily remain in that branch. They may pass into the 



