DEVELOPMENT OF THE COMMON PROG. Ill 



Plate XVIII. 



73 (3). An enlarged view of the larger of the two 

 tadpoles (Plate XVII. 73), showing the liver and coiled 

 intestine, was made. On the removal of these viscera, the 

 lungs, as represented on Plate XVII. 73 (2), were exposed 

 and the drawing of them made. 



74. The tadpoles continued to feed eagerly on the meat. 



Among those taken this morning one had four legs ; 

 the shape of its body was frog-like, which seemed to 

 depend on development of the skeleton, as seen in the 

 form of the head and back. Another tadpole was taken 

 in which the fore legs remained under the skin, but were 

 on the point of being pushed out. Drawings of both were 

 made, the natural size. 



74 (2). An enlarged drawing was made of the ventral 

 surface of the four-legged tadpole. It showed that the 

 left fore leg had passed through the opening of the gill- 

 chambers, whilst on the right side there was a distinct, 

 well-defined, round hole, through which the right fore leg 

 had come out. This, however, is not shown in the view 

 given. 



74 (3)- On removing the skin from the ventral surface 

 the gills were exposed, and were nnusnally distinct. A 

 broad band of cartilage extended across the chest imme- 

 diately behind them, and united the fore legs. The abdo- 

 men was small, and tightly bound in by a purplish sheet 

 of membrane which was marked by a darker line down the 

 middle from the centre of the shoulder- girdle to the pubes. 

 The enlarged drawing represents these parts. 



74 (4). By removing the purple fascia the liver and 

 intestine were exposed to view, and appeared as represented 

 in the drawing, the coil of the intestine being wonderfully 

 diminished in size. 



