306 



W. M. BALDWIN. 



mass. The mesenchymal tissue to either side of the neural 

 tube and notochord presents normal features. 



Comparable to the levels represented by Figs. 7 and 9 is the 

 section represented by Fig. 12. Here again the flexure of the 

 neural tube lies dorsal to the notochord sections. Immediately 



FIG. 12. 



ventral to the latter the forms of the elongated myoblasts are 

 to be made out. A relatively early stage of development of the 

 enteron is evidenced by the condition of the yolk cells, the sym- 

 metrical masses of which are separated by the deep epidermal 

 cleft. 



In the succeeding four figures, 13, 14, 15 and 16, embryos are 



FIG. 13. 



FIG. 14. 



represented in each of which the angularity of the flexure was 

 not sufficient to bring the long axis of the two body portions 

 parallel to each other. In each instance, the cephalic extremity 



