INJURIOUS TO CUCUMBER, SQUASH AND MELON 135 

 The Melon Aphis 



Aphis gossypii Glover 



This insect is also known as the cucumber aphis, cantaloupe 

 aphis, cotton aphis and orange aphis. When occurring in green- 

 houses, it is known to gardeners as black aphis or black fly. 

 It is widely distributed throughout the United States but has 

 been reported as a serious enemy of cucurbits from Minnesota 

 to New Jersey and southward. Its range extends to Brazil. 

 It has attracted most attention in those localities where melons 

 or cucumbers are grown on a large scale and in such cases the 

 losses are often very great. It sometimes becomes of con- 

 siderable importance as a cotton pest. The melon aphis has a 

 wide range of Avild food plants, including many common weeds 

 and is occasionally found on a number of cultivated plants, 

 such as spinach, okra, tomato, asparagus, eggplant, hop, 

 morning-glory, bean and beet. 



The life history of the melon aphis has not been fully worked 

 out and there is considerable difference of opinion as to how 

 the insect passes the winter. It has been commonly supposed 

 that winter eggs are produced in the fall and deposited on 

 some food plant that will survive the winter. In fact eggs 

 found on portulaca and strawberry have been described as 

 belonging to this species. Great doubt has been cast on this 

 view by the studies of Sanborn, who has shown that in Okla- 

 homa the insect is unable to survive the winter in the open, 

 and that each year it migrates northward from southern Texas, 

 where it breeds continuously the year round. If it is true that 

 the melon aphis does not winter over in the northern part 

 of its range and that the infestation is annually renewed by 

 migrants from the South, its habits in this respect are very 

 similar to those of the famous green-bug of wheat, Toxoptera 

 graminum. 



