G. H. F. Nuttall 
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end where it rests upon the glass. Thus, in ten tubes containing felt 
strips, some females laid 131 eggs of which 87 were attached to the 
bottom of the strips, 36 at the lower edge, and 8 at the sides within 
0-5 cm. from the bottom. This observation led me to make the follow¬ 
ing experiments: 
Expt. 1. A felt strip (Fig. 7 A) from the bottom of which a pin 
projected to a distance of T5 mm., was placed pin end down in a tube. 
The felt therefore did not rest directly on the glass. Lice placed in 
the tube laid 12 eggs at the bottom of the strip and 2 eggs near the 
lower edge. 
Expt. 2. As lice are prone to hide in the seams of clothing it was 
thought that by pinning two strips of felt together like an inverted Y 
(resting the ends on two pins to prevent the contact between the glass 
Fig. 7. Illustrating the arrangement of the felt strips used in experiments 1 and 2. 
The strips rest on pins projecting below, the strips being maintained vertically in the 
tube by pins traversing the felt crosswise. Natural size. 
and felt, see Fig. 7 B) the insects would perhaps prefer to lay in the cleft. 
Contrary to expectation the females laid 11 eggs at the bottom of one 
strip, 6 near by at the sides, and only 3 in the cleft but near the bottom 
of the second strip. That the eggs were laid at the bottom of one strip 
only, serves as a good example of the “homing instinct” presently 
to be described. 
Expt. 3. A felt strip was placed horizontally about 2-5 mm. away 
from the bottom of a tube, a few pendant filaments permitted the insect 
to climb up on the felt from below. A female laid 4 eggs, all on the 
more filamentous sides of the felt. 
Expt. 4. A felt disc accurately fitting a tube was inserted as a 
floor and a strip was pinned horizontally above it at a distance of 
about 3 mm. Some pendant filaments extended from the strip to the 
