99 
Webster's experiments indicate that the caterpillars can be killed 
at once in a clover stack by the use of pyrethrum. He had five tons 
of clover restacked, dusting it with this insect powder, using ten 
pounds of pyrethrum to fifty pounds of flour, and found in a sample 
of the hay that the majority of the caterpillars were dead the day after. 
Britton, in Connecticut, tried bisulfid of carbon in a stack and 
hydrocyanic acid gas in a barn, but in both instances the clover had 
become packed so solidly that only a few caterpillars — those on the 
outer part of the heap — were killed by the treatment. 
We need to know more about the life history and habits of this 
insect notwithstanding the large number of articles that have been 
written on the species, for these, with a few exceptions, add nothing 
to Riley's original account of 1874. 
Hypsopygia costalis Fab. 
1874. Riley, C. V.— Sixth Rep. Ins. Mo., pp. 102-107. 
1891. Webster, F. M.— Insect Life, Vol. IV., pp. 121, 122. 
1894. Davis, G. C— Bull. No. 116, Alich. Agr. Exper. Sta., pp. 
56-58. 
1896. Lintner, J. A.— Eleventh Rep. Ins. N. Y., pp. 145-151. 
1901. Britton, W. E. — Twenty- fourth Rep. Conn. Agr. Exper. 
Sta., 1900, p. 314. 
Clover Lkaf-midge 
Dasyneura trifolii Low 
( Cecidomyia trifolii) 
This midge deserves some attention on account of its conspicuous 
effects on the leaflets of white clover, the leaflet being folded in halves 
along the midrib to form a sort of pod, which turns yellowish and at 
length brownish. Within this pod can be found white or orange mag- 
gots, or silken cocoons. The maggots change to minute flies — so small 
and inconspicuous as to interest only a specialist. 
The economic importance of the leaf-midge is small, however, 
and nothing has been added to our published knowledge of the species 
since Comstock's account of 1880. Some new information appears in 
the present paper. 
The species, long known in Europe, has been recorded from 
Washington, D. C. ; it occurs also in Illinois, and in all probability is 
present in many other parts of the country. 
Food Plants. — The leaf-midge feeds on white clover. In Europe 
it has been said to affect the undermost root-leaves of red clover, but 
I have not as yet been able to find it on that plant in this region. 
The maggot does not fold the leaflet ; the egg is laid before the 
leaflet has opened out, and after the larvcC begin to work the leaflet 
remains closed. It grows to a normal size, however, (PI. II., V\g. 4 I 
and continues to be green for a time, but eventually turns yellowish 
near the midrib, where the leaflet bulges out here and there, blisterlike. 
