102 ranaDjE. 



cavity, and concealed by a little operculum of the integu- 

 ment. The eyes are now perfectly formed. The holders have 

 become much diminished in size ; the mouth has acquired 

 moveable lips, and has changed its position from the in- 

 ferior part of the head to near the extremity, and the little 

 creature which has hitherto derived its sustenance either 

 from its own resources or by absorption, now seeks its food 

 amid softened and decomposing vegetable matter. The 

 caudal web (fig. 8) has, therefore, become considerably de- 

 veloped, and serves for very rapid as well as varied loco- 

 motion. The colour of the body, too, has undergone a 

 considerable change, having become of a soft olive green, 

 the abdomen being dotted with golden yellow. 



The Tadpole now undergoes but little change in its ex- 

 ternal form for a considerable time, but increases rapidly in 

 bulk, and by and by a little tubercle appears on each side 

 of the vent, which is the rudiment of the posterior extre- 

 mity ; this soon acquires somewhat the form of the perfect 

 limb, the toes budding, as it were, at the extremity, but it 

 still continues very short, even in proportion to the dimi- 

 nutive size of the animal (fig. 10). Meanwhile the anterior 

 extremities are also budding forth in the same manner, and 

 gradually assume their distinct and final form. 



As the hinder extremities become developed, the tail, the 

 former organ of progression, is removed by absorption, not 

 thrown off, as has been erroneously stated. This is a gra- 

 dual process, the absorption beginning at the apex, and pro- 

 gressing onwards to the base, until the whole is removed ; 

 so that the posterior part of the body becomes rounded, 

 and the cloacal opening, instead of being placed beneath, 

 is directed somewhat upwards. Fig. 11 exhibits the 

 young Frog with a small portion of the tail still remaining 

 unabsorbed. 



