THE CANADIAN ENTOMOLOGIST. 159 



by the emerging insect and leaves its contents on the forehead. Pupae in 

 which fully formed moths had died without emerging show, on dissection, 

 the empty cell with a sediment adhering to the forehead of the insect not 

 only in J. polypheimis, but in A. yama-mai and other species of Antherea 

 I have been able to examine in this condition. 



With a view of determining the question, I prepared a number of 

 polyphemus cocoons by removing the outer layers and cutting a narrow 

 slit on opposite sides to near the head, so that when suspended in the 

 light the motions might be watched, and in two instances have been able 

 to see, though rather imperfectly, the whole performance. As before 

 stated, the moth on breaking the pupa-skin carries on its forehead a drop 

 of liquid, which, as the moth lengthens itself in the effort to free the fore 

 legs, is smeared upon the end of the cocoon, and during the twisting and 

 squirming accompanying this effort, well rubbed in. After freeing the legs 

 the moth rests for a moment ; then, pushing up one shoulder, turns 

 several times in the cocoon, the shoulder being pressed against the smeared 

 part. The result of this appears to be to loosen some of the fibres, for 

 after two or three repetitions of this movement, the legs are extended 

 upward and the abdomen extended, forcing the shoulders more firmly 

 against the cocoon and a vigorous clawing begun ; this is succeeded by a 

 butting movement, the abdominal segments being first retracted and then 

 forcibly extended, followed by more twisting, clawing and butting, until a 

 small hole is made, when the butting movements predominate and the 

 moth finally emerges, pushing the cut ends of the threads outward. 



So far as I have been able to observe, the hooks in the wings merely 

 serve to detach the fibres and hold them in place until broken by the 

 powerful legs, the removal of the gum and weakening of the silk by the 

 liquid on the head rendering this comparatively easy — this possibly being 

 aided by the surplus fluids of the pupa being brought up during the 

 retraction and extension I have called " butting," but whether this is 

 really the case or not I am unable to" 1 state. A similar cell is observable 

 in all pupae of this family, and it seems probable that they all emerge in 

 the same manner, employing neither wholly chemical nor mechanical 

 means, but both. 



Note. — It is but fair to add that since these notes were prepared I 

 have seen mention of a paper by Mr. Packard on the same subject, but 

 as it is not in general circulation, have been unable to see the paper in 

 question. 



