AMPHIBIA AND REPTILIA OF COLORADO 257 



Family Hylidae 



Chorophilus triseriatus Wied 



Three-lined Tree Frog (Figs. 1-4) 



Boulder, May i-io, 1914; near Alma, Park County, above 10,000 ft., August, 1914 

 (493)- 



Eggs and adults of this little frog were taken in temporary pools 

 formed by the melting snow along a railroad right-of-way near 

 Boulder, during the first ten days of May, 1914. On May 9 eggs 

 were collected in the four-celled stage and kept out of doors in water 

 from the pool in which they were found. The development of these 

 eggs was very rapid, a fact which may be correlated with the use of 

 temporary pools as the spawning grounds by this species. On the nth 

 all of the eggs were in the elongated stage preceding hatching, and 

 during the 1 2th most of the eggs hatched. The tadpoles of Chorophilus 

 triseriatus immediately after leaving the eggs were very black and 

 about 8 mm. in length, resembling the tadpoles of the common toad 

 in outline. 



Since the adults of this species were so abundant about the pools 

 near the University during the spring spawning season, a study of the 

 variation in the color pattern was made. The color pattern has been 

 used by several writers in connection with certain anatomical char- 

 acters for the separation of the subspecies of Chorophilus nigritus 

 LeConte, and Chorophilus triseriatus (Wied) is considered as one of 

 these subspecies by some writers. The data collected from 40 adults 

 taken from a single pool about ten feet across, are given below: 



Back with stripes only; spots if present, on the eyelids only 9 



No spots on the eyelids i 



Spot on each eyelid free 5 



Spot on each eyelid fused with the mid-dorsal stripe 3 



Stripes and spots both present on the back 27 



No spots on the eyelids 2 



Spot on each eyelid free 15 



Spot on each eyelid fused with mid-dorsal stripe 10 



Spots only 4 



No spots on the eyelids i 



Spot on each eyelid 3 



