98 



SCHOOL ENTOMOLOGY 



In the northern part of its range it feeds on prickly 

 ash (Xanthoxylori) . 



59. Pieridae. This group includes all our common yel- 

 low and white butterflies. They are mostly of medium 



to small size and may at 

 times be injurious. There are 

 many species, but only a few 

 which are important. The 

 larvae are usually green and 

 are not conspicuous. The pupae 

 resemble those of the Papilios, 

 but have only one pointed 

 projection from the anterior 

 end of the body and are, of 

 course, smaller. The best- 

 known species is the " imported 

 cabbage-worm" or Cabbage 

 Butterfly.* There are other 

 native and imported species 

 which closely resemble this 

 one in general appearance and 

 habits. 



The more common yellows 

 are the Clover Butterflies or 

 " sulphurs " of which there are 

 many species. Their larvae may 



be found in clover fields and one species seems to be 

 becoming a pest in alfalfa fields. Several kinds, smaller 

 than the ordinary clover butterflies may be noted. Among 

 these will be the Dainty Sulphur. The largest of our Pierids 

 is a beautiful insect with wings of pure unmarked sulphur 

 yellow, It is called the Cloudless sulphur. Another 

 * See page 282, Part II. 



FIG 72. Larva of Papilio 

 cresphontes. 



