The Southern Tree Frog 



Disks on fingers and toes well developed. Inner sole tubercle 

 small; no outer sole tubercle. Tubercles under joints of toes 

 somewhat prominent. Webs short. (See Figs. 173 to 177.) 



Range'. Hyla squirella Bosc is found in the southern part of 

 North America, its range extending well up the Mississippi. It is 

 reported from North Carolina, South Carolina, Georgia, Florida, 

 Louisiana, Mississippi, Texas, and southern Indiana. 



Hyla squirella is a delicate, smooth-skinned, little tree frog, 

 and is one of the most active in North America. It is a most 

 difficult frog to catch, giving leap after leap in rapid succession and 

 in changing directions. If we do succeed in catching a half a dozen 

 and carry them home in a pail or box, there are few chances but 

 that we shall lose most of them the moment they are uncovered. 

 They do not wait to be lifted out; they do not climb onto one's 

 finger and cling confidingly; they jump simultaneously with the 

 opening of the box, all in different directions. 



Of all the tree frogs of North America, this one has perhaps 

 the greatest power for rapid colour change, and during these 

 changes presents the greatest variety of colours and shades of 

 colour. At any given moment Hyla squirella may wear any one 

 of the following costumes : unspotted dark chocolate brown or dark 

 brownish olive; light purplish brown with dark brown spots; 

 light yellowish or greyish brown without spots; any medium 

 shade of brown with green spots; olive green unspotted; light 

 yellow green spotted with brown; unspotted light pea-green; 

 light greenish gray ; light fawn colour, or still lighter shades rang- 

 ing down to flesh colour. 



Most curious is the fact that although these changes take 

 place under the influence of various stimuli, such as light, moisture, 

 and heat, they may go on without these stimuli. Frogs shut in 

 a dark pail with no change of conditions will not appear twice 

 alike when the pail is opened at intervals during the space of sev- 

 eral hours. Some may be green and others brown; some spotted, 

 others not; some ight while others are dark. And at any given 

 time of observation those that were dull and spotted before may 

 be bright unspotted green, the ones that were light may be dark, 

 and so on. The light line along the jaw undergoes great changes 



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