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, $. 
(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, $, 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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