MINING CATERPILLARS. 237 



polyanthus, one of those mining-caterpillars may very 

 frequently be found. It is, however, considerably 

 different from the preceding, for there is no black 

 trace — no river to the valley which it excavates : its 

 ejectamenta, being small and solid, are seen, when the 

 leaf is dried, in little black points like grains of sand. 

 This miner, also, seems more partial than the pre- 

 ceding to the midrib and its vicinity, in consequence 

 of which its path is seldom so tortuous, and often 

 appears at its extremity to terminate in an area, com- 

 paratively extensive, arising from its recrossing its 

 previous tracks.* 



Leaf of the Primrose (Primula veris), mined by a caterpillar. 

 Swammerdam describes a mining caterpillar which 

 he found on the leaves of the alder, though it did 

 not, like those we have just described, excavate a 

 winding gallery ; it kept upon the same spot, and 

 formed only an irregular area. A moth was pro- 

 duced from this, whose upper wings, he says, 

 " shone and glittered most gloriously with crescents 

 of gold, silver, and brown, surrounded by borders of 

 delicate black." Another area miner which he found 

 on the leaves of willows, as many as seventeen on 

 one leaf, producing what appeared to be rusty spots, 

 was metamorphosed into a very minute weevil 

 (Curculio Rhinoc). He says he has been informed, 



