38 



PRACTICAL ZOOLOGY 



pupa;, and finally emerge as adults. Paris green, an arsenical 

 preparation, has proved to be a practical and effective 

 remedy, for when sprinkled on the potato plants this poison 

 is taken into the beetle's stomach with the leaves and quickly 

 kills it. 



Cabbage Worm. — The cabbage worm (Fig. 20, C) is the 

 caterpillar of the cabbage butterfly. It is not indigenous to this 

 country but was unintentionally introduced from Europe about 



1S60, when it first 

 appeared near 

 Quebec, Canada. 

 By 1S6S it had 

 reached the Gulf 

 States; since then it 

 has made its way all 

 over the country. 

 The cabbage butter- 

 fly (Fig. 20, A) is 

 white with black 

 near the tip of the 

 fore wings, and is 

 about two inches 

 across when the 

 wings are expanded. 

 The larva; (Fig. 20, 

 C) are velvety green 

 in color and resemble the foliage so closely as to be hardly 

 distinguishable from it. When full-grown thev are about one 

 and one fourth inches long. Spraying or dusting with Paris 

 green will kill the larva;, but some people are afraid to do this 

 for fear of being poisoned when they eat the cabbage. This 

 fear, however, is unfounded, since one would have to eat twenty- 

 eight entire heads at one sitting to feel any poisonous effects 

 from the Paris green. Many cabbage worms are annually de- 

 stroyed by parasites, one of which, a Braconid fly, is especially 



Fig. 



butterfly : A, adult ; 

 D, pupa or chrysalis. 



