6 
INSECTS INJURIOUS TO SUGAR CANE. 
of Lachnosterna fusca, var. puncticollis, which was also found by Mr. 
Howard alive and hibernating in the earth among the stubble. The 
soil in every condition of cultivation in injured localities was carefully 
examined, with no results so far as Ligyrus was concerned, and we can 
say with considerable certainty that the insect in any stage of growth 
is not to be found in the fields during the winter. The most natural 
supposition after this conclusion is that the metamorphoses are under- 
gone in the surrounding swamps, and that the adult beetles make their 
appearance in early spring and fly to the cane plantations. 
But contrary to this conclusion is the following fact: On May 22 Mr. 
W. J. Thompson, of Calumet plantation, Bayou Teche, sent to the de- 
partment, among other insects collected at the roots of cane where the 
beetles were very abundant, a few very young white grubs, of a species 
different from any sent by any other correspondent, and also differing 
from any which have been found since. These were placed in a breed- 
ing-cage under roots of grass. On August 2 one of the grubs was ob- 
served to have changed to a pupa in an oval cavity two or three inches 
below the grass roots, and on August 24 a crippled beetle was found in 
the cage, which, though badly deformed, seems without doubt to be a 
true cane beetle. Of course this single instance needs confirmation, 
and we would earnestly request that during the months of June and 
J uly search should be made among the roots of cane, and that all white 
grubs found be forwarded to the department for rearing. 
CHARACTER OF FIELDS MOST INJURED. 
It was puzzling at first to account for the fact that the injuries of the 
beetles were confined to certain sections of fields, or to plantations the 
surroundings of which and the method of cultivation in which seemed 
identical with non-injured sections, but it was noticed that there was 
quite a marked difference in the character of the soil, that of the in- 
jured portions being more sandy and friable, while that of the other 
parts was of the common heavy, clayey, alluvial soil — soil in which the 
experienced person on turning it over would at once reject the idea of 
finding insects. The former, found only upon the highest parts of the 
plantation, is soft and loose, easy to burrow in, and when examined is 
found teeming with insect life. Mr. Swamsteadt’s plantation, the one 
worst damaged, is remarkable for this peculiarity of the soil ; while all 
the testimony so far gathered upon this point seems to confirm the fact 
that Ligyrus works almost exclusively on cane grown in soil of this char- 
acter. 
One of our correspondents made mention of the fact that previous to 
1880 rattoon cane had been principally damaged, while in that year both 
rattoon and plant were equally eaten. This fact it was which first sug- 
gested the idea that the beetles bred at the cane roots, and, hibernating 
in the stubble, naturally first appeared there and did most harm. The 
explanation of the fact probably is, however, that in ordinary seasons 
the beetle appears before the cane is up, and takes to stubble as the only 
