i66 A NATURALIST IN THE GREAT LAKES REGION 



nymph, anglewing, mourning cloak, red admiral, Edward's hair- 

 streak, the zebra swallowtail, and the spicebush swallowtail, etc. 

 The tree frogs, Hyla versicolor (Fig. 173) and H. pickeringii (Fig. 

 174), are common on the shrubs and tree trunks. They are so 

 striking an addition with their birdlike peeps that the black oak- 

 red oak association is known on its animal side as the Hylodes 

 association. The walking stick is frequently shaken from the 

 foliage of the oak in late summer. The tree cricket, Oecanthus 

 angustipennis , and stinkbug are also com^monly found on the 

 red oak leaves. The former is a pale green insect with gauzy 

 wings and long antennae wath black dots on the basal joints of 

 the antennae. The red-tailed and red-shouldered hawks sail 

 over this territory and nest in the big trees. The red-headed 

 woodpecker, wood pewee, crow, blue jay, bluebird, least fly- 

 catcher nest in the trees, and the black and white creeping war- 

 bler, the yellow warbler, the wood thrush nest in the shrubs. 

 The gray and fox squirrels are present. 



All these animals of the hylodes association, while strikingly 

 new if this zone is entered from the lake side, are old familiars 

 if the area is approached from the other direction, for they are 

 all even more common in the mixed oak-hickory association. 

 The oak-hickory and the maple-beech forests are the climax 

 mesophytic forests and will be considered in a succeeding 

 chapter. 



