252 ENTOMOLOGICAL NEWS. [Oct., '03 



The Feeding Habits of the Larva of 

 Anthocharis genutia. 



BY HERMAN HORNIG, Philadelphia. 



With the first days in -May, when Spring calls flowers and 

 insects into active life, the Mouse ear cress, Sisymbrium tha- 

 liana stands ready to receive its few callers. Its modest ap- 

 pearance is usually overlooked by the High School Girl botan- 

 izing, who -is more ...charmed by sweet smelling Pink's and 

 Crowfoot violets often growing side by side with thaliana, 

 One of its life duties is "to be the sustenance of our orange tip 

 butterfly, Anthocharis genutia. It is around its blossoms that 

 the pretty little pairs get acquainted and the courting begins. 

 The female -selects a leaf, stem or cluster of flowers to deposit 

 the orange-colored egg, and spends the remaining days sip- 

 ping here and there from the little white flowers. 



Each little axillary bud which thaliana sends forth has the 

 appearance and color of the newly-laid egg to deceive the 

 seeker for the new inhabitant. One of the duties of genutia 

 is the fertilization of the flower which grows into a long 

 slender seedpod, usually carrying a tiny sepal along, like a 

 little flag, till it is finally lost. The newly hatched genutia 

 walks along till a slender stem is reached, at whose end is the 

 seedpod, " the spread table," and the first meal is taken. By 

 some unobserved means the larva also carries a speck of sub- 

 stance on its baqk, and as the feeding commences at the stem 

 end of the pod and the larva mooves into the space it has 

 made by eating, the detection of the little animal by the collec- 

 tor is mostdifficult, as the colors of the pod and worm are exactly 

 the same. This applies only to the first stages, as later on the 

 dimensions of the larva, its dark back and underside somewhat 

 alter the circumstances. The pupa is of peculiar shape and 

 found on the bark of trees and stones. One of the great ene- 

 mies of the larva is a little black spider which has a few threads 

 of silk attached from the blossoms to the end of the seedpods. 



Eggs of genutia are seldom found in numbers on one plant. 

 As a rule there is only one egg on a plant, although two have 

 been collected on large, healthy specimens, abundant for miles 

 around Westville, N. J. 



