FIELD BOOK OF INSECTS. 



which develop into the small, delicate, green moths you 

 may have noticed about the lights, cover themselves with 

 bits of their food ; when next you gather Black-eyed Susans 

 and Field Daisies look carefully on the flowers for a collec- 

 tion of petals fastened to the back of a Geometrid larva 

 (Plate LVIII). The name of this family means "earth 

 measurers" and in English we call the larvae Measuring- 

 worms, Inch-worms, Span-worms, or Loopers. The 

 saying that, when they walk on our clothes, they are 

 planning a new suit for us is probably as logical as "earth- 

 measuring" and more interesting to us personally. Their 

 peculiar locomotion is due to their lacking all but two or 

 three pairs of abdominal legs; with legs only at each end 

 of the body they must hump themselves to get along. 

 The adults are slender-bodied; their wings are broad and 

 the pattern on the front wing is, in many cases, continued 

 on the hind wings. Nearly a thousand species have been 

 described from this country alone. 



Imagine a tiny gray flower-pot having 



A pa a gray cover decorated with a dark central 



pometana . 



spot and a dark ring near the edge; that is 



like an egg of the Fall Canker-worm, which also goes 

 under the generic name of Anisopteryx. The female 

 (Plate LVIII) places several hundred of them in a flat 

 mass, keeping the rows regular, on the bark of almost 

 any deciduous tree. This is usually done in Novem- 

 ber but sometimes not until spring. The larvae, es- 

 pecially at first, skeletonize the leaves instead of eating 

 them entirely; they get to be about an inch long, are 

 black and have, on each side, a stripe of yellow below the 

 spiracles and three narrower whitish stripes above them. 

 These larvae, like many of their relatives, often let them- 

 selves part- way down to the ground by means of a silken 

 thread. If it is not your tree, it is rather amusing to see 

 them climb up this thread again, for all the world like a 

 sailor going up a rope. Once, about the first of June, they 

 do not go back but instead go to a depth of from one to 

 four inches underground, where they spin a thin, tough 

 cocoon, pupate, and remain until October, November, or 

 the next spring. The adult males are brownish-gray and 



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