214 THE FROG CHAP, xn 



given in a subsequent chapter. But if you wish to make the attempt, 

 proceed as follows : — 



Take out a few eggs every day from the time they are laid until the 

 tadpoles are hatched : place these on a tile or piece of glass, and with a 

 pair of needles dissect off the gelatinous covering. Then carefiilly transfer 

 the segmenting eggs or embryos into corrosive sublimate for a quarter 

 to half an hour, and after washing in running water, put them into 

 weak and then strong alcohol ; then stain, imbed, and cut sections as 

 directed on p. 136. 



