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A Cave Crustacean in a Well. 



A friend of mine has a splendid well of water with a force pump in it. The water 

 is always cool and has been clear until now. Lately it throws forth plenty of the in- 

 closed specimens. Are they not Phylopods, or the Ear-wig, or is this the Lithobius, 

 the crawling fellow we find in our house once in a while ! Tell me all about it and 

 how to clear the well. — [J. M. Shaffer, Keokuk, Iowa. 



Reply. — I beg to acknowledge the receipt of yours of the 19th instant, with speci- 

 men of an animal found in a well. This is the little crustacean described by Packard 

 as Cwcidotea stygia and which has been found in Mammoth and other caves, in the 

 little pools of clear cold water which abound in such locations. You will iiud a 

 very good figure of this species, with an account of its habits, in the third volume 

 of the American Entomologist, pages 35-36 (February, 1880). 



Potato Stalk-borer in Corn and Rag- weed. 



Mr. O. J. Voorhees brings me this morniug samples of growing corn nearly a foot 

 high which are being destroyed by larva uuknown to me. I understand that the 

 cornfields are largely infested. Will you please describe fully ? Have you knowledge 

 of a remedy ? If so state it fully that it may be published for the common good. — 

 [J. M. Shaffer, Keokuk, Iowa. 



Reply. — The worm which you send and which infests corn in your vicinity is the 

 larva of a common Stalk-borer (Gortyna nilela Guen). This insect is a very gen- 

 eral feeder and ravages not only corn but other cereals and also potatoes, toma- 

 toes and a number of flowering plants which are commonly grown in gardens. By 

 way of compensation it is particularly partial to the stem of the Cockle Bur (XantJiium 

 sti'umarium). On account of its diversity of food plant, and on account of its feed- 

 ing on the interior of the stalk, it is a most difficult insect to fight. The only remedy 

 which has ever been proposed, and the only one which will result in any practical 

 results, consists in cutting the larvse out of the stalks which are observed to wilt from 

 its attacks. This of course would be a most tedious operation in large quantities, but 

 it is the only way to lessen the number of worms. The labor of boys could be readily 

 utilized in this work. It has been previously recorded as damaging corn, but I think 

 never to the extent which you describe. 



Another letter. — As you request, I to-day send you a box containing a larva of the 

 corn-stalk borer, marked No. 1, and three larvae of what appears to be the same, which 

 I found in rag-weed stalks, marked No. 2. In the corn they are rare at this seasou, but 

 are rather common in the rag-weed. On the 29th ultimo I noticed one stalk where the 

 borer had eaten out and left. In large corn they enter the stalk a few inches above 

 the ground, and eat across nearly to the opposite side, and then upward. The first 

 time I ever saw the borer was in 1832, in a piece of ground that had been pastured 

 more than twenty years, and never plowed until that spring. There were quite a 

 good many of them. The next year I had corn on the same ground aud there were a 

 few again. These were all near the edge of the field. This year I have corn on the 

 same piece again, and they were all over it. Oue day about the 1st of June, I killed 

 about fifty worms, and many more at other times. In 1884 I fouud a few in rag-weed 

 along the edge of this same field, when it was in oats. This spriug I fouud a few in 

 another field over a quarter of a mile from the other infested ground. Others in the 

 neigbborhood are not troubled with them to any great extent. The most of their 

 work is done when the corn is from 2 to 10 inches high, and before it begins to joint. 

 Then the heart is eaten out just above the root, leaving the outside of the stalk green. 

 The infested stalks may be known by the central blades being dead. This is the best 

 time to destroy them. They are then from i inch to 1 inch long, and are easily killed 

 by pulling the infested stalks up and crushing them.— [Thomas Wikessell, Wauseon, 

 Ohio. 



