Geometridae 



It is the only species of the genus found within our territory. It 

 is not uncommon in the Appalachian subregion. 



Genus NYCTOBIA Hulst 



Three species belong to this genus. One of them is selected 

 for illustration. 



(i) Nyctobia limitata Walker, Plate XLII, Fig. 22, $. 



Syn. lobophorata Walker ; vernata Packard. 



The habitat of this moth is identical with that of the last-men- 

 tioned species. It is not at all uncommon in Pennsylvania. 



Genus CLADORA Hulst 



(1) Cladora atroliturata Walker, Plate XLII, Fig. 23, S. 

 (The Scribbler.) 



Syn. geminata Grote & Robinson. 



A neatly marked species, which is the sole representative of 

 the genus in our fauna. The moths may be found in the early 

 spring seated upon the trunks of trees in the forest. It is a native 

 of the Appalachian subregion. 



Genus RACHELA Hulst 



Four species of this genus have been characterized by the late 

 Dr. Hulst. The only one which occurs in the eastern portions 

 of the continent we figure. 



(1) Rachela bruceata Hulst, Plate XLII, Fig. 24, $ . 



The moth is found in the northern Atlantic States. It is not 

 uncommon in western Pennsylvania. 



SUBFAMILY HYDRIOMENIN/E 

 Genus PALEACRITA Riley 



There are reputed to be three species of the genus found in 

 the United States. Only one of them, because of its economic 

 importance, has received much attention thus far. 



(1) Paleacrita vernata Peck, Plate XLII, Fig. 25, S , Fig. 26, 

 $ . (The Spring Canker-worm.) 



Syn. sericeiferata Walker ; autumnata Packard ; merricata Dyar. 



There are two insects known as canker-worms. One of 

 these, the smaller of the two, is properly named the Spring 



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