INSECTS INJURIOUS TO MELONS, CUCUMBERS, ETC. 341 



this season they seem to feed on almost anything, as they 

 have been observed feeding on a long list of food-plants, frequent- 

 ing flowers whose petals are eaten. As soon as squash, melons, 

 or cucumbers break through the soil, they gather upon them 

 and refuse all other food. If the foliage is covered with any 

 offensive substance they will seek out 

 spots which have not been reached and 

 feed upon them, which fact is of im- 

 portance in considering remedies. After 

 feeding upon cucurbs for a few days the 

 beetles pair and the females 'commence 

 to deposit eggs. The eggs are deposited 

 singly and are merely dropped in crev- 

 ices of the soil or in the opening around 

 the stem of the plant. The egg is oval, 

 about one-fortieth inch long, bright yel- 

 low, and sculptured with microscopic 

 hexagonal pits. A female lays about 

 one hundred eggs during a period of a 

 month, and they hatch in about eight 

 days at a mean temperature of 74 F. 

 The larva is a slender, white, worm-like 

 grub, about three-tenths inch long, with 

 dark -brown head and anal-plate, and lighter brown thorax. The 

 larvae bore into the roots, often tunneling into the base of the stem, 

 and sometimes mine into melons lying on damp soil. Rarely does 

 injury by the larvae become noticeable, though we have observed 

 whole patches of cucumber and melon vines killed by them, which 

 seems remarkable, considering the immense numbers of the beetles 

 which must give rise to many times more larvae. The larva 

 becomes full grown in about a month and then forms a delicate 

 earthen cell just below the surface of the soil and in it transforms 

 to the whitish pupa, from which the beetle emerges in from one to 

 two weeks, according to the temperature. In southern New 

 Hampshire the beetles emerge from the last of August to the first of 

 October, the complete life cycle requiring from seven to nine weeks, 

 there being but one generation a year, and this seems to be true 

 in New York. In Kentucky the complete cycle requires but 

 thirty-nine days, and in the District of Columbia newly emerged 



FIG. 288. Larva of strip- 

 ed cucumber beetle at 

 work in cucumber stem. 

 (Photo by Headlee.) 



