168 



THE RATE OF GROWTH 



[CH. 



The growth of the tadpole * is Hkewise marked by epochs of 

 retardation, and finally by a sudden and drastic change (Fig. 37). 

 There is a shght diminuti9n in weight immediately after the little 

 larva frees itself from what remains of the egg ; there is a retardation 



10 20 30 40 50 60 70 80 90 



days 



Fig. 37. Growth in weight of tadpole. From Ostwald, after Schaper. 



of growth about ten days later, when the external gills disappear; and 

 finally the complete metamorphosis, with the loss of the tail, the growth 

 of the legs and the end of branchial respiration, brings about a loss 

 of weight amounting to wellnigh half the weight of the full-grown 



* Cf. (int. at.) Barfurth, Versiiche iiber die Verwandlung der Froschlarven 

 Arch. f. mikroak. Anat. xxix, 1887.* 



