109 
2. Roots evidently injured or destroyed by perforations, gnaw¬ 
ing’, burrowing, decay, or other loss of substance, 
a. Roots eaten away, not burrowed or perforated, and 
without rotten or withered tips. Tap-root commonly 
gone or decayed. White grubs in soil among or be¬ 
neath the roots. 
THE WHITE GRUBS. 
Genera Lachnosterna and Cyclocephala. 
(Plate XII., Fig. 1-8; and Plate XIII., Fig. 1 and 2.) 
White grubs or “grub worms” are among the immemorial 
enemies of agriculture on both sides of the Atlantic, and in both 
Europe and America the problem presented by their injuries on 
the farm and in the fruit and vegetable garden still calls for 
thoroughgoing investigation and scientific treatment. In fact, 
the steady increase of their numbers in this State—probably con¬ 
nected with the gradual enlargement of the area laid down in 
grass—has made such an investigation of their life histories, 
habits, and economic relations simply imperative and indispen¬ 
sable. 
They infest a great variety of plants, nearly all of which have 
an agricultural value, many of them being the great staple crops 
of the farm and garden. ~Grasses of every kind, all the small 
grains, Indian corn, potatoes, beets, and the root crops gener¬ 
ally are liable to destruction by them, as well as strawberries 
and young fruit trees, young evergreens, larches, and young 
forest trees of various kinds. 
Like most other injurious insects of the first class, they are 
liable to great variation and fluctuation of numbers in different 
localities and in successive years, sometimes getting the tempo¬ 
rary mastery of a considerable tract, appropriating nearly its 
whole growth of vegetation to their own use, and then, within 
a year or two, disappearing from view for a time as an injuri¬ 
ous agency. Apart from these seemingly spontaneous fluctua¬ 
tions of numbers, they are most likely to cause great loss when 
the crop on ground infested by them is changed by rotation from 
one affording them an abundance of food to one yielding a rela¬ 
tively scanty growth—as when grass lands are planted to corn. 
A number of grubs which would produce no visible effect in a 
dense sward, may be sufficient to devour completely a field of 
young corn. 
They hatch most commonly in grass lands (although fre¬ 
quently also in corn), from eggs laid there by various kinds of 
