THE NARCISSUS- OR DAFFODIL-FLY. 



185 



with hairs, those on the front portion being black, and those at the 

 tip being grey or reddish yellow. The legs are of moderate length, 

 and are black and hairy. This insect is scarcely half an inch in 

 length, and measures about an inch across the wings when they are 

 spread open. The grubs are about half an inch long ; they are of an 

 oval shape and smooth, but the joints of the body are well marked ; 

 they are of a dirty yellowish-white colour. The pupa or chrysalis 

 very much resembles the grub ; it is much wrinkled, but there are 

 no definite divisions of the body. Bulbs that are imported are 

 occasionally infested with these grubs, but they may generally be 

 detected by pinching them at the neck, when, if they contain a grub, 

 they will feel soft and spongy. A friend of mine some years ago 

 reported in the Garden newspaper that he purchased an apparently 

 promising lot of 200 Narcissi at a sale, but he found no less than 

 eighty grubs in them. The flies may be found flying about and 

 settling on the bulbs in May and June ; * when this is noticed every 

 effort should be made to catch them. Many may be caught in a 

 butterfly net after a little practice ; it has been suggested that they 

 may be caught by placing plates filled with treacle, and the edges 

 smeared with honey, near the bulbs. The flies will be attracted by the 

 smell of the honey and get caught in the treacle. It is obvious that 

 nothing can be done to kill the grubs without destroying the bulbs ; 

 that, however, would not matter, for if the grub has so far destroyed 

 the bulb as to make its presence known the bulb is sure to die. 

 Dr. K. Bos, the celebrated Dutch naturalist, suggests as a precaution 

 that all bulbs that are at all likely to be infested should be immersed 

 in water for at least eight days, so as to drown the grubs. I feel 

 rather doubtful of the utility of this measure, as I do not think the 

 water would soak in far enough, and there would probably be sufficient 

 air in the bulb for the requirements of the grub, and at the time when 

 the bulbs are planted the grubs would be so small that they would 

 not have done much damage to the bulbs. If the water in which 

 the bulbs were placed could be kept at a temperature of about 

 115° Fahr. for twenty minutes or half an hour, the heat would 

 probably kill the grubs without injuring the bulbs. — G. S. S. 



* This year (1902) they were abundant in the early partrof July.— W. W. 



