oa 
Fig. 1. Moth of Orchard Tent-caterpillar. 
ENTOMOLOGY. é 369 
ENTOMOLOGY. 
TEN T-CATERPILLARS. 
PROF. OTTO LUGGER, ST. ANTHONY PARK, 
The past year has been remarkable for the large number of some species 
of insects not usually so very abundant in our state. Among these the 
caterpillars of the ‘‘Tent-caterpillar of the Forest” (Clisiocampa sylvati- 
ca) deserve special notice, as they were found in some parts of the state 
in such immense numbers as actually to stop the railroad cars in several 
instances. 
It is remarkable that these bright and showy caterpillars should appear 
suddenly in such vast numbers, without first becoming decidedly apparent 
during the spring of the previous year. Yet such was the case. During 
the spring of 1890 the common Orchard Tent-caterpillars (Clisiocampa 
americana) abounded near the Experiment Station, but a careful search 
for the allied species failed to reveal any of them, nor were any found 
elsewhere. It is true the differences between these two species is slight, 
as may be seen in the illustrations before you, yet they are sufficiently 
\ 
\\ \ 
IF y 
Fig. 2. Early stages of Orchard Tent-caterpillar: 
a, b, caterpillars resting upon tent-like nest: 
c, ring-like egg mass; d, cocoon. 
—24 
