Figure 1-4 is a cross section of one of the ocular muscles of a frog at the metamorphosis 

 (82 days after fertilisation). Note how the developing fibrils have encroached 

 upon the myosyncytium, leaving merely a clear zone between each bundle. 

 In these clear zones is shown the development of the sarcolemma, which is there- 

 fore formed in situ and not from special mesenchyme tissue introduced from 

 without. Note that some of the nuclei are imbedded within the bundles of 

 muscle fibrils while others lie to one side. X 1000. 



