TWO INSECTS OF THE ORCHARD — SNODGRASS. 



495 



cies carries the mining instinct further than does the shield-bearer, 

 for it not only spends all of its caterpillar life in the mine, passing 

 the winter thus in the dead leaf, but it pupates in the mine, coming 

 out only as the adult moth. The trumpet miner, furthermore, takes 

 more pride in the character of its mine than do most other leaf 

 miners, the Avails being lined with smooth white silk and all refuse 

 discharged through trapdoors in the floor, so that the interior is 

 kept fresh and clean. Still another species, the serpentine miner 

 (fig. 5, A), is, as the shield-bearer, a miner only during its larval 

 life. But when it leaves the mine it comes out naked and crawls off 

 to a twig, where it spins a cocoon of silk for its pupal period, as 

 does any ordinary caterpillar. A fourth species, the ribbed-cocoon- 

 maker, is less of a miner than any of these, since it tunnels into the 

 leaf during only the first stage of its caterpillar life, after which it 



Fio. 6.- — The Cigar Case-Bearer. .1, thp winter case ; B, C, the caterpillar in its spring 

 case, consisting of the winter case with additions at the lower end ; D, the same cater- 

 pillar with new cigar-shaped case (a) feeding within a small mine in a leaf from lower 

 end of case ; b, a deserted feeding mine. 



feeds openly on the surfaces of the leaves, finally spinning a re- 

 markable fluted cocoon in which to pupate. 



On the other hand, there are species that specialize as case makers, 

 neglecting the art of mining or discarding it entirely. Two well 

 known examples are the cigar case-bearer and the pistol case-bearer. 

 The former mines into the leaf when very young to cut out a case 

 which it thereafter wears as a suit of armor, traveling about in it 

 and feeding from its lower end. During winter it hibernates in this 

 case (fig. 6, A) after firmly attaching it to the bark. In spring the 

 caterpillar becomes active again, adding frills of leaf cuttings to the 

 lower end of its case as it grows (B, C), but soon is forced to cut 

 out a new one to accommodate its increased size. This second case 

 (D, a) is long and cigar-shaped, whence the wearer gets its name. 

 The caterpillar feeds by burrowing into the leaf only as far as it 



