METAMORPHOSES OF INSECTS. tfi* 



ent species, being dotted, or sprinkled, with yellow and 

 black, instead of having the colors well defined. If 

 the young naturalist will take a sprig of the parsley with 

 one of these on it, and put the whole into a glass jar, or 

 other place of confinement, taking care to water the 

 plant, he will soon find it to be identical with the large 

 ones. 



100. This larva is remarkable for having on the back 

 of the neck, an instrument composed of two fleshy horns, 

 branching from a common stem somewhat like the letter 

 Y. This organ appears to be similar in some respects to 

 the horns of snails, and is capable of similar movements, 

 being completely retractile. When the animal is irritated 

 these horns are projected, and it appears from the observa- 

 tion of Reaumur, that this organ secretes an acid liquor, 

 which emits the unpleasant smell, and which every one 

 who has touched one of these worms, cannot but have 

 perceived. Reaumur supposes that this acid is a means 

 of defence against the attacks of the ichneumon, a small 

 fly which deposites its eggs in the flesh of the larvae of 

 various insects. 



101. This larva, when spinning the silken cord by which 

 it is to be supported in the F 'S- 27. Fig. 28. 

 chrysalis state, invariably 



fixes it round the neck at 

 the junction of the fifth and 

 sixth segments, where there 

 is a cavity in which it is 

 kept from sliding backward 

 or forward. This cord ap- 

 pears to pass under the skin 

 of the chrysalis, but on ex- 

 amination with a magnifier, 

 it will be seen, only almost 

 concealed in a deep chan- 

 nel. The larva and its 

 chrysalis, both of the natur- 

 al size, are represented by Figs. 27 and 28 j the latter be- 

 ing suspended by the cord in the manner described. 



102. Difference in the chrysalids of butterflies and 

 moths. There are differences between the chrysalids of 



