A MINING PROPOSITION. 



Breakfast was late one hot morning 

 last August. So we walked out on the 

 porch to possess our souls in patience 

 as best we could. There was no need 

 of hurry after all. At the end of the 

 porch was a luxuriant growth of wild 

 clematis. We idly sauntered up to it 

 and picked off a leaf, which we were 

 just about to throw away when our at- 

 tention was taken by some queer mark- 

 ings upon it. What was the matter 

 with it? In fact, what was the matter 

 with most of the leaves on the vine? 

 Brownish serpentine lines were on all 

 of them, each beginning in a small, 

 round spot which curved out, widening 

 as they progressed. Some were short, 

 some were several inches long. What 

 could they be? Not marks on the leaf, 

 but something inside; we could see a 

 tiny tunnel, with a thin roof over its 

 length. We seated ourselves on the 

 steps and went to work to solve the 

 mystery, with a pin for a dissecting in- 

 strument. No lens was at hand, but 

 perhaps sharp eyes would do. We 

 started with a big tunnel. Sure enough, 

 the roof was the delicate upper epi- 

 dermis of the leaf; something had dug 

 out the green parenchyma cells leaving 

 the lower epidermis intact for the floor 

 of the excavation. It must be some- 

 thing very tiny indeed to find room to 

 work between the upper and lower 

 edges of a leaf. We would follow up 

 the tunnel and find the miniature work- 

 er. The chase grew exciting, as the 

 clumsy pin tore away slowly the deli- 

 cate tissue of the roof. Finally the en- 

 larged end was reached and there was 



the miner, the tiniest little white grub 

 or caterpillar snugly curled up, and al- 

 most too small to be seen with the 

 naked eye. 



Now it was all clear, going back the 

 other way, the ever narrowing tunnel 

 ended, or rather began, in a little round 

 spot. It was a case of circumstantial 

 evidence. Some mother insect had laid 

 a speck of an egg in the leaf under the 

 epidermis. The larva emerged and 

 ate the food at hand, the green cells. 

 When this was gone, it ate on forward 

 in a winding line, till now, its appetite 

 appeased, it was ready to turn into a 

 pupa. To confirm our suspicions of the 

 parentage of this little miner, we now 

 noticed the presence of several minute 

 moths flying here and there over the 

 leaves as if looking for places to deposit 

 more eggs which should hatch into 

 more miners and make more blotches 

 on our clematis vine. 



It was a long time after breakfast 

 was finally eaten that we found out the 

 family history of the leaf miners. There 

 are many of them, so say the insect 

 books, and each species mines a dif- 

 ferent kind of a leaf. Some mines are 

 long and narrow, and these are called 

 the linear. Some are narrow at the be- 

 ginning and enlarge rapidly and curve, 

 and so they get the name of trumpet 

 mines. Those which we investigated 

 are the serpentine. Some leaf miners 

 are flies, some are beetles, but most of 

 them., like ours, are tiny moths, the pig- 

 mies of their race, to whom a leaf of- 

 fers an ample field for operations. 



Ruth Marshall. 



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