ESSAY ON ONIONS. 91 



time the bottoming commences. We have heard their appearance 

 charged to the use of muscle-bed, — but whether they are hmited to 

 land on which muscle-bed has been used, we cannot say. We think 

 not. We think they are natural associates of the plant. The effect 

 of them is to diminish the quantity, but not to materially injure the 

 quality of the vegetable. 



The crop is sometimes injured by a blue mould that gathers on the 

 tops, occasioned by fogs, or an excess of moisture from frequent and 

 long continued rains. 



There is a ivorm or maggot, occasionally found upon the onion 

 plant, in the early stages of its growth, causing it to turn yellow and 

 die. This insect will be found in the bulb, originating from eggs laid 

 upon the leaves, by a small ash colored fly, the scientific name of 

 which is said to be Antliomyia ceparum (See Transactions of the N. 

 Y. State Agr. Soc. for 1843, page 135.) It comes to maturity in 

 less than a month ; so that there may be several generations in the 

 course of the season. Their appeance in this vicinity is rare. Pul- 

 verized charcoal and fire have beenTound the most effectual remedies, 

 against the ravages of this class of depredators. 



The most annoying enemy of the onion, is the cut worm, or grub 

 worm. It probably is the same described by Dr. Harris, in his Re- 

 port on the Insects of Mass. injurious to vegetation, page 324, 

 there called ^^Agrotis devastator." And in the 1st vol. of Silli- 

 man's Jour, of Science, ^^Phaloena noctua devastator;''^ though Dr. 

 Harris does not mention the onio7i as among the plants upon which 

 it feeds ; probably considering it, like tobacco as too noisome to be 

 used by any decently civilized being. They are said "to seek 

 their food in the night, or in cloudy weather, and retire before sun- 

 rise into the ground, or beneath stones or any substance which can 

 shelter them from the rays of the sun ; here they remain coiled up 

 during the day, except while devouring their food, which they drag 

 into their places of concealment." The remedy for these worms, 

 suggested by our cultivators, corresponds nearly with that proposed 

 by IVIi-. Foote of Berkshire, "ifo catch them and pull their teeth 

 out.'''' This being effectually done to all, their operations will be 

 of a limited character. When this is omitted, we have sometimes 

 known whole fields almost entirely cut down by these rapacious de- 

 vourers. They sweep clean where they go, not suffering even the 

 weeds or any other herbage to flourish. They are more frequently 



