The Cabbage-caterpillar 



grubs nibble the wallets whence they have just 

 emerged. By to-morrow, nothing is left of 

 these but a pattern of round dots, the bases 

 of the vanished sacks. 



As his first mouthfuls, therefore, the Cab- 

 bage-caterpillar eats the membranous wrapper 

 of his egg. This is a regulation diet, for I 

 have never seen one of the little grubs allow 

 itself to be tempted by the adjacent green 

 stuff before finishing the ritual repast whereat 

 skin bottles furnish forth the feast. It is the 

 first time that I have seen a larva make a meal 

 of the sack in which it was born. Of what 

 use can this singular fare be to the budding 

 caterpillar? I suspect as follows: the leaves of 

 the cabbage are waxed and slippery surfaces 

 and nearly always slant considerably. To 

 graze on them without risking a fall, which 

 would be fatal in earliest childhood, is hardly 

 possible unless with moorings that afford a 

 steady support. What is needed is bits of silk 

 stretched along the road as fast as progress is 

 made, something for the legs to grip, some- 

 thing to provide a good anchorage even when 

 the grub is upside down. The silk-tubes, 

 where those moorings are manufactured, must 

 be very scantily supplied in a tiny, new-born 



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