THE LEPIDOPTERA OR BUTTERFLIES AND MOTHS 21 



coiled up like a watch spring under the head may be 

 straightened out into a long " tongue " by which the butter- 

 fly sucks the nectar from flowers. The sucker is formed of 

 the parts of two modified maxillae which have been enor- 

 mously lengthened and closely fitted together. Their 

 inner faces are concave so that a tube is formed when the 

 two parts are applied. The mandibles in the butterflies 

 are either represented by minute rudiments or absent 

 entirely. There is little left of the labium except the two 

 labial palps which project in front of the head. 



The butterfly lays its eggs upon the leaves of the cabbage 

 or some other related plant. Watch the butterflies as 

 they flit about in a cabbage patch and you will probably 

 see them alighting for a short time upon the leaves. Note 

 'carefully the spot where the butterfly rested; look at it 

 with a hand lens and you may find a small oblong egg 

 stuck by one end to the leaf. The egg soon hatches into 

 a small green larva which is colored so nearly like the green 

 leaves that it is often difficult to detect. The larva has 

 mouth parts fitted for chewing, much like those of the 

 grasshopper, the mandibles being particularly strong. 

 There are three pairs of legs on the thorax; and on certain 

 segments of the abdomen there are short, stubby legs 

 called pro-legs, whose ends are furnished with minute 

 hooks which aid the caterpillar in maintaining its hold 

 on the surface of a leaf. The larva sheds its skin a number 

 of times during its growth, and at its last molt passes into 

 the pupa stage. It does not spin a cocoon as is done by 

 many moth larvae, but the pupa is fastened to some object 

 by a thread which passes around the thorax. At the tip 

 of the abdomen of the pupa there is an organ, the cremaster, 

 which is furnished with booklets for attaching to a small 

 pad of silk which the larva spins just before transforming 

 into the pupa. 



