72 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
mostly at evening and during the night, though I have occasionally 
heard it early in the morning and in the late afternoon. 
13. Hyla pickeringii (Storer). Pickering’s Hyla. 
This delicate little frog is very abundant in the woods and groves, 
especially in the damp, deciduous woods of beech, birch, and aspen, 
along the bases of the mountains. It seems to live mostly well up 
in the trees, whence its shrill cries are often heard. After July, it 
seems to get more noisy in the woods, and may be heard at almost 
all hours of the day. These frogs appear inactive during the night, 
though I have heard their notes in early September until about 
7.30 p. m. 
They are hard to find, as they will frequently, after uttering a 
few notes, stop piping and remain silent for long intervals. They 
are occasionally found hopping about in the woods, and at such 
times can be captured with little difficulty, though they are almost 
as nimble as wood frogs. Apparently they can change their color 
only to a limited extent, by making the X-mark on the back and 
the other darker markings change from a rich yellow-brown to a 
gray so pale as to be almost indistinguishable from the ground 
color of the back. When jumping from one leaf to another, or 
to any vertical surface, they will always come to rest with the 
head pointing up. When placed in a bottle, and then turned so 
as to be upside down, they will always turn around until the ver¬ 
tical position, with the head up, is reached. 
14. Hyla versicolor Leconte. Tree Toad. 
Abundant in groves, orchards, and shade trees from the river 
valley into the woods, though apparently commonest in the more 
open areas between the river and the woods. During June and 
early July, it is heard tooting from the trees on every side, dur¬ 
ing the warm evenings. As the summer advances it is less often 
heard, and during August and September only an occasional 
note is sounded.. It sings mostly during the evening and night, 
though after a shower during the day, its notes may be heard. I 
have also occasionally heard it in the woods at noon, on hot sunny 
days. 
I once found one on the intervale, squatting on a large, dark 
colored rock, under an oak. It looked very much like a thick 
piece of lichen and had turned a grayish white color. It was cling¬ 
ing to the rock with head lowered, and feet tucked in close to the 
body, so that at first I was completely deceived, and only on 
attempting to remove the lichen, did I discover it. 
