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The same method of making the marks, which it is not necessary 

 to enter into here, was followed as has been described elsewhere for 

 the eggs of Spelerpes. After several marks had been made about the 

 equator of the egg, as in diagram A, the eggs were set aside and 

 examined at intervals. On the whole, the experiments were not very 

 successful, due to a variety of causes. Nevertheless, a sufficient number 

 of well marked eggs developed to show that the process of blastopore 

 closure was not essentially different from that of Spelerpes. In all 

 cases where the marks moved at all, they extended into bands, ap- 

 proximately equal in length, which ran parallel with the meridians 



Diagram A. Egg from the lower pole, shortly before the appearance of the blasto- 

 pore, showing tbe position of the blue spots. Only half of each spot is visible. 



Diagram B. Egg from the lower pole, when the blastopore has nearly closed 

 showing the blue bands resulting from the extension of the spots figured in diagram A. 



from the equator of the egg toward the lower pole to the edge of the 

 circular blastopore: diagram B. The artificial bands of blue pigment, 

 then, gave the same appearance to the egg as the natural dark bands 

 already described. 



Similar results were obtained from the frog's eggs. The eggs of 

 this species are similar in color to the eggs of Amblystoma, but are 

 much smaller. The movement of the brown pigment, too, appeared to 

 be similar to that of Amblystoma, though it was not especially studied. 



These frog's eggs appeared to be quite sensitive to the injurious 

 effects of the stain, which, in the case of Spelerpes, is of negligible 

 amount. This may be due to their smaller size, accompanied by the 



