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50,000 in number, set late in June. These have been attacked and many j 
of them destroyed by the adults of two species of Rhynchophora {Lis- p 1 
tronotus appendiculattis Boh. and Erycus puncticollis Lee). The former b 
is supposed to be the chief depredator, though I myself t aw the latter d 
attacking the plants. First, great cavities are gouged out of the stems n 
of the young plants, and later the bases of the larger leaves are attacked t 
from beneath. Both secrete themselves in the ground about the plants, t 
and I took ten individuals of the Listronotus from about a single plant. I 
It is not unlikely that one and perhaps both of these species breed in 
Sagittaria, though I have some reasons for suspecting that the Erycus 
may breed in the common Typlia latifolia or cat-tail. 
A minute Thrips, in all probability Limotlirips tritici Pack., as 
determined by Mr. Th. Pergande, through the courtesy of Mr. How- 
ard, U. S. Entomologist, has caused serious injury to the onion crop, 
seeming to be very generally distributed over the State. This little 
pest appears to breed in enormous numbers among the tops of the 
onions, well down toward the crown of the plant, where the close prox- 
imity of the young, tender growth renders destructive measures well 
nigh impractical, and, besides, places the young Thrips beyond the 
reach of the majority of its natural enemies. Still, continual repro- 
duction compels the little pests to sooner or later leave their coverts, 
especially after reaching maturity, and they are then devoured by the 
swarms of little red and black ladybirds (Megilla maculata De G.), 
which, judging from the number of them present in the onion fields, 
must exert a powerful influence in holding the pest in check during 
ordinary years. The most useful parasite, however, is the larva of a 
small Syrphus fly belonging to a species not yet determined. These 
maggots are to be found down among the younger portions of the 
tops, near the crown, and right in the midst of the young Thrips, which 
they devour precisely as aphides. We have found that applica- 
tions of a strong decoction of tobacco water, or a mixture of 1 part 
crude carbolic acid to 100 parts water killed all that -were in reach, 
but so many are so entirely protected in their secluded nooks in the 
crown of the plant that repeated applications are necessary. For 
some reason the injury has been more emphatic on the higher lands. 
In the vicinity of Lodi, Ohio, there are several hundreds of acres of 
onions, cultivated for the most part on redeemed swamp lands where 
the soil is of a peaty nature, but with an occasional knoll of clay. 
Comparatively little injury has been done on the low, wet, peaty 
soil, while on the clay the destruction is almost total. 
A number of years ago, while living in Indiana, I observed adults of 
Ligyrus gibbosus De G. depredating on carrots in the fields. This 
year the same insect came to me likewise from Indiana, accused of 
destroying sunflowers by eating the roots, going from hill to hill to 
continue their depredations. This character has been recorded of the 
species west of the Mississippi River, but not, I believe, farther east. 
