The Cabbage-caterpillar 



quires the indications provided by the flower. 

 Here the Pieris surpasses us. She does not 

 consult the seed-vessel, to see if it be long or 

 short, nor yet the petals, four in number and 

 arranged in a cross, because the plant, as a 

 rule, is not in flower; and still she recognizes 

 off-hand what suits her caterpillars, in spite 

 of profound differences that would embarrass 

 any but a botanical expert. 



Unless the Pieris has an innate power of 

 discrimination to guide her, it is impossible 

 to understand the great extent of her vegetable 

 realm. She needs for her family Cruciferae, 

 nothing but Cniciferas; and she knows this 

 group of plants to perfection. I have been an 

 enthusiastic botanist for half a century and 

 more. Nevertheless, to discover if this or 

 that plant, new to me, is or is not one of the 

 Cruciferae, in the absence of flowers and fruits 

 I should have more faith in the Butterfly's 

 statements than in all the learned records of 

 the books. Where science is apt to make 

 mistakes, instinct is infallible. 



The Pieris has two families a year: one in 

 April and May, the oth^r in September. The 

 cabbage-patches are renewed in those same 

 months. The Butterfly's calendar taUies with 



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