Gr. H. F. Nuttall 
139 
(A) Corporis. 
Expl. 1 (20-24. ii. 1917). A square of thick dark blue woollen 
cloth, rough on one side and smooth on the other, measuring 7-5 x 6 cm., 
was placed rough side up upon the bottom of a circular glass dish of 
corresponding size. A small platform of glass, measuring ca. 1 x 1-5 cm., 
was laid in the centre of the cloth and the orientation of the latter noted. 
d c c Y d 
Fig. 8. Illustrating the experiment on “homing instinct” in regard to oviposition in 
Pediculus humanus ( corporis ) described in the text, (ri) the smooth and ( B ) the 
rough side of the cloth. Natural size. 
In the accompanying figure (Fig. 8) the smooth underside of the 
cloth is indicated by the letter A, the rough upper side by the letter B. 
The female was fed twice daily, being removed from the cloth for the 
purpose. After each feeding she was replaced upon the platform and 
returned to the thermostat maintained at 32° C. The cloth, whose 
corners are marked a, b, c, cl in the figure, was inspected twice daily 
whilst the female was being fed. 
