INSECTS ATTACKING CUCURBITACEOUS PLANTS. 807 



This insect is distributed throughout the eastern half of the 

 United States from Canada south to Mexico, and is thought to 

 be a tropical species. The female lays eggs singly on the squash 

 plant during June or early July in Connecticut, but may be abroad 

 at a much earlier date farther south. The eggs are usually laid 

 on the stem, but may often be found on the leaves or buds. The 

 eggs are oval "and dull red, and over two hundred may be laid 

 by one moth. From one to two weeks are required for the eggs 

 to hatch, and the larvse become full grown in about four weeks. 

 The newly hatched larva enters the main stem, where it tunnels 

 through it lengthwise near the base, often going into the leaf 

 petioles which branch from the main stem. As the larvae increase 

 in size they eat more and more each day, and the plant begins 

 to wilt. This is usually the first sign of the attack, though an 

 earlier examination would show the yellowish excrement which 

 is thrown out of the holes in the stem. The stem usually begins 

 to decay near its base, and is often severed at this point. The 

 full-grown larva is about one inch long, rather stout and soft, 

 is white with a black head and is shown with its injury on Plate 

 L. It goes into the ground one or two inches, where it makes a 

 cocoon of silk, to which adhere small particles of soil. There 

 is only one generation each year in Connecticut, but in Washing- 

 ton, D. C, there are two broods. 



In our experiments several remedies have been tried, including 

 wrapping the stems with tarred paper, placing tarred paper disks 

 around the stems at the base, and painting the stems with a thick 

 mixture of lead arsenate. These three practices did not seem 

 worth while. The only treatment that we can recommend is to 

 plant early squashes for traps to be destroyed later ; to cut into 

 the stems, making a longitudinal incision, and killing the borers ; 

 to cover the stem with earth one or two feet from the base to 

 induce secondary roots that will support the plant in case it should 

 become severed at the base. It is also advisable to destroy all old 

 vines as soon as the crop is secured. 



The Striped Cucumber Beetle. 

 Diabrotica vittata Fabr. 



A frequent and serious enemy of all cucurbits is the striped 

 cucumber beetle, Diabrotica vittata. Soon after the seedling 



