EDUARD UHLENHUTH 



353 



which they were kept during the larval period). Two breeding fe- 

 males, collected recently outdoors, measured 112 mm. and 106 

 mm. respectively.^^ Cope,^^ j^ his book on North American batra- 

 chians, mentions the specimen, from which he described the species, 

 as measuring 3.8 inches (about 100 mm,). The largest animal found 

 in the collection of the American Museum of Natural History^'' meas- 

 ured 117.7 mm.; the average of the eight largest animals was 100.3 

 mm. 



Mm. 

 130 



110 



90 

 70 

 50 



30 



5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 65 90 95 



Weeks 

 Fig. 2. Experiment 1 (Ambystonia opaaim, 1918, Series XIV). The unbroken 

 line indicates the growth of the controls, the dotted line that of the anterior 

 lobe-fed animals. 



To conclude from these data the maximum size of the species is 

 nearly 118 mm., while specimens measuring more than 115 mm. are 

 of very rare occurrence. 



" I am obliged to Mr. George P. Engelhardt, of the Brooklyn Museum, for 

 this record. 



^^ Cope, E. D., The batrachia of North America, Washington, 1889. 



^•^ I wish to express my appreciation to Miss M. Dickerson for giving me the 

 opportunity of examining the collection of salamanders at the American Museum 

 of Natural History. 



