156 



NUTRITION AND GROWTH OF LARVAE 



o 



X 

 0. 



o 

 < 



5 



• - liver food 

 fspinoch a 

 1 liver food 



100 120 



TIME — DAYS 



Effect of diet on time of metamorphosis. The number 

 of completely metamorphosed tadpoles is plotted against 

 time in days after fertilization. 



From Briggs G Davidson 1942: Jour. Exp. Zool. 90:401 



The kidney stones produced from oxalic acid of spinach and found commonly among the 

 frog tadpoles at metamorphosis (Briggs & Davidson, 1942) are not seriously damaging, 

 and spinach seems to carry the forms to metamorphosis more rapidly than any other 

 diet. Daphnia and then Enchytrea have proven to be the best for Urodele larvae, with 

 small strips of liver being offered after metamorphosis. 



ififrinum 



JO »o TO eo 



Growth curves for tigrinurij and punctatum larvae raised 

 under similar environmental conditions but on different 

 diets. Vertical lines indicate the beginning of feeding. 



From Hutchinson G Hewitt 1935; Jour. Exp. Zool. 71:465. 



