State Agricultural Society. 
537 
it lias a strong tendency to tear them from their attachment, and the 
worm shows particular care in fastening the ends securely, applying 
its mouth to the surface at numerous points to glue the thread 
thereto, whereby a dense web comes to be formed upon the surface 
around each end of the loop. The- worm, moreover, moves its body 
from side to side with each thread that is spun. When a thread is 
about being fastened upon the right side, to give the mouth the requi¬ 
site room for attaching it* to the surface, the body is crowded to the 
left, as far as the threads already spun will admit, thus putting these 
threads on the stretch, whereby the worm will ascertain if it is fasten¬ 
ing them sufficiently secure. 
Having completed its skein of threads the larva straightens itself, 
and it is then noticed that about two-thirds of its length is forward of 
the skein. It now becomes quiet and motionless, but its body gradu¬ 
ally contracts in length, whereby at the end of an hour or two its 
anterior part is found to be but half as long as it previouly was, the 
skein now girting it around its middle. It has also undergone a 
sensible change in its form, that portion which is forward of the girt 
being thicker and cylindrical whilst that which is back ot it is gently 
tapered. 
The larva remains in this position, with its hind feet fastened into 
the little hillock of silk threads at the end of its body and the loop 
around its middle, from twenty to thirty hours. Then, with some 
writhings and contortions a cleft is opened in the skin on the upper 
side of its neck, which crack soon extends along the middle of the 
head and the fore part of the back, forming an oriiiee of sufficient size 
to allow the body to pass out through it, and when the head is also 
disengaged it rests upon the old skin of the larva. The pupa now 
by contracting and elongating itself rapidly crowds the skin back¬ 
ward crumpling it together underneath its body, until only the 
conical hind part remains upon the pupa. Being securclyffield by the 
loop of silk which is now around it, the pupa readily withdraws the 
tapering hind end of its body from the remainder of the larva skin, 
and the tip of its body being furnished underside with a number of 
minute hooks, it pushes these backward beyond the shriveled 
remains of the larva skin, and fastens them into the little wad of silk 
threads to which the larva skin is also attached by the minute hooks 
of the hind feet. This larva skin being now a crumpled mass of 
membrane and hairs, discommodes the pupa by being crowded as it 
is under and around the hind end of its body. In order to remove it 
therefore, the end of its body being bent into a curve at this time 
Ag. 68 
