THE FROG. 309 



midwife, and promotes the expulsion of the eggs by work- 

 ing' with his thumbs, arid compressing the female's body 

 more closely. The eggs which were compressed in the 

 womb, upon being emitted, expand themselves into a 

 round form, and drop to the bottom of the water : while 

 the male swims off", and strikes with his arms as usual, 

 though they had continued so long in a state of violent con- 

 traction. 



The egg, or little black globe, which produces a tadpole, 

 is surrounded w r ith two different kinds of liquor. That 

 which immediately surrounds the globe is clear and trans- 

 parent, and contained in its proper membrane; that which 

 surrounds the whole is muddy and mucus. The transpa- 

 rent liquor serves for the nourishment of the tadpole from 

 time to time ; and answers the same purposes that the 

 white of the egg does to birds. The tadpoles, when this 

 membrane is broken, are found to adhere with their mouth 

 to part of it; and when they get free, they immediately 

 sink to the bottom of the water, never being able to get to 

 the top after, while they continue in their tadpole form. 



But to return : When the spawn is emitted and impreg- 

 nated by the male, it drops as was said, to the bottom, 

 and there the white quickly and sensibly increases. The 

 eggs, which during the four first hours suffer no percepti- 

 ble change, begin then to enlarge and grow lighter; by 

 w r hich means they mount to the surface of the water. At 

 the end of eight hours, the white in which they swim grows 

 thicker, the eggs lose their blackness, and, as they increase 

 in size, somewhat of their spherical form. The twenty- 

 first day, the egg is seen to open a little on one side, and 

 the beginning of a tail to peep out, which becomes more 

 and more distinct every day. 



The thirty-ninth day f the little animal begins to have 

 motion ; it moves, at intervals, its tail; and it is perceived 

 that the liquor in which it is circumfused, serves it for 

 nourishment. In two days more, some of these little crea- 



