38 ART. 3. — S. IK EDA : CONTRIBUTIONS 



that the coincidence, where it exists, is in itself of no funda- 

 mental significance " (p. 413). 



In order to test this point further, I made the following 

 observations on Rhacophorus eggs. I took eggs either before, or 

 just after, the first appearance of the first cleavage line and fixed 

 them, each on a cover-glass, in the manner already described at 

 the beginning of the article, by heating it slightly on the edge of 

 a sand-bath for about 30 seconds. The eggs were put as quickly 

 as possible in a vessel full of water, and reared in the usual 

 way. As soon as the first cleavage appeared, its direction was 

 plainly marked on the cover-glass by two points. In this way, 

 I prepared four groups of eggs. 



In the first groiq), only one egg out of five was found to have 

 been well fixed on the cover-glass : the rest unfortunately fell 

 off. In the single egg, the axis of the embryo, when it appeared, 

 was exactly at right angles with the plane of the first cleavage. 



In the second group, three eggs out of five were well fixed. 

 In the first of these the embryonic axis (the head end) was 

 inclined 50° to the right of the first cleavage plane. In the 

 second egg, the embryonic axis was at right angles, to the first 

 cleavage plane. In the third, the anterior half of the embryo 

 was at right angles to the first cleavage plane, while the posterior 

 half was somewhat oblique and deflected about 30° to the left 

 from the embryonic plane. The main axis of the embryo must, 

 however, be considered to be at right angles to the first cleavage 

 plane. 



In the third group, only three out of ten eggs were found 

 to have been well attached to the cover-glasses. In one of the 

 three, the inclination of the embryonic axis to the first cleavage 

 plane was about 50°, and in another 20° to the right. In the 



