CHAPTER I. 

 GENERAL ANATOMY OP THE FROG. 





Fig. 1. The Common Frog {Rana temporaria) : (from Ecker.) 



A. External Characters. 



La^ the frog on a hoard before you ; note, and make drawings^ 

 showing the follovmig points : 



1. The division into head, trunk, and hmbs ; and the absence 

 of neck and tail. 



2. The two great surfaces. 



a. The dorsal surface, or back, is directed upwards when 



the frog is in the natural position. 

 h. The ventral surface, or belly, is directed downwards 



towards the ground. 



