COPEIA 29 



it), have made me hesitate in publishing these notes, 

 but I will give them for what they are worth. 



Practically all the specimens studied came from 

 a spring near Haverford, Pa., in which spring both 

 adults and larvae were very abundant, and ten or fif- 

 teen could be caught at any time. Some of the larvae 

 were much larger than small adults, my smallest 

 adults being 80-90 mm. long and my largest larvae 

 about 110 mm. long. These larvae were distinguish- 

 able from those of S. bisUneatus, by much larger size 

 and uniform coloration. The smallest seen were as 

 long (50-60 mm.) as the largest larvae of S. bisUnea- 

 tus seen and much more robust. 



In January of this year I started keeping the lar- 

 vae alive with a view to watching the transformation. 

 I continued this into the spring with no success, the 

 larvae all dying in a few days, or living on with no 

 signs of transformation. 



However, in a series of ten larvae collected on 

 May 20, the largest (110 mm.) showed tinges of red 

 in the ground color and smaller gills. On May 22 

 this specimen had lost all the filaments of the gills and 

 had taken to lying entirely out of water. 



May 23 — The gill stumps were shrivelling, the 

 tail fin had gone, and the color was more like that of 

 the adult. A smaller one of the same lot of May 20 

 (90 mm.) had also lost the tail fin and showed a red- 

 dish tinge. The gill filaments also were smaller. 



31 ay 24 — A (the large one) gills were stubs- 

 eyelid developed — mouth nearly developed — B (the 

 smaller one) eyelids developing — mouth developing 

 — gill filaments ragged. 



May 27 — A, mouth developed fully — tongue 

 free, gills mere stubs. 



May 28 — I collected an adult which showed un- 

 mistakable signs of having just completed the trans- 

 formation. 



