176 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 13 
possible to find some individuals in each of the groups which could 
not be properly classified by means of the circumgenital pores alone. 
There is also a considerable variation in the averages of lots belonging 
to the same form, but these variations are not so great as to render it 
even doubtful as to which form each of the lots belongs. 
The differences which have been noted in these forms are sum¬ 
marized below: 
Brown or apple form 
Yellowish-brown form 
Grayish-brown or banded 
form 
Uniform in color 
Posterior half of scale lighter 
in color with yellowish 
hue 
Brown crossed with three 
grayish bands 
Weathered scales very dark 
Weathered scales very dark 
Weathered scales bluish- 
white 
Double-brooded 
Double-brooded 
Single-brooded 
Parasitized 
Parasitized 
Not parasitized 
Infests apple 
Probably does not infest 
apple 
Does not infest apple 
Probably does not infest 
poplar 
Infests poplar 
Infests poplar 
Infests pear, peach, plum, 
hackberry and horse- 
chestnut 
Does not infest pear, peach, 
plum, hackberry and 
horse-chestnut 
Average number of circum¬ 
genital pores, 73.1 
Average number of circum¬ 
genital pores, 83.3 
Average number of circum¬ 
genital pores, 104.1 
We are not in a position to offer any definite suggestion as to the 
systematic relation of the different forms, but the one that infests the 
apple is no doubt identical with the European form, Lepidosaphes ulmi. 
The yellowish-brown form should probably be considered as a variety 
of Lepidosaphes ulmi Linneus. The grayish-brown or banded form 
may possibly be only a variety of Lepidosaphes ulmi , but it seems more 
probable that specific characteristics will yet be found which will make 
it possible to describe it as a separate species, or possibly to identify 
it as one of the other European species already described. The fact 
that it infests mainly artificial plantings, indicates that it has come to 
us in the nursery trade and probably from Europe. 
At present the economic importance of the banded form is of greater 
concern than its systematic relations. As a fruit pest it is of no conse¬ 
quence, but in cities it is now much more abundant in Illinois than 
either of the other forms, and from the published records of the oyster- 
