MOUNTING SPIDERS. 29 
paper, otherwise the hairs are apt to drop off. Then, holding 
the larva in the left hand, enlarge the vent slightly below with 
a vertical cut of the scissors, and next press the extremity 
of the body with the fingers so as to force out the contents 
of the rectum ; repeat the operation a little farther forward, 
and so on, a slight additional portion of the contents of the 
body being gently pressed out each time. Great care should 
be exercised not to abrade the skin or get the exterior soiled 
by the expelled pertions. When a portion of the intestine 
is extended, it should be seized with the forceps and, hold- 
ing the head in the left hand, the tube should be forcibly 
but steadily torn from its attachments bringing with it most 
of the contents of the body. 
The lamp is now lighted and placed under the oven; and 
a straw taken of a proper size to enter the enlarged vent ; 
having cut off one end diagonally it is moistened and 
carefully inserted into the opening for about a quarter of an 
inch, and then pinned through the straw and anal plate with 
a delicate insect pin. The caterpillar is then inflated with the 
breath, taking care not to use too great a pressure, and then 
extended horizontally in the oven, the inflation being con- 
stantly continued. ‘The posterior end should be dried first 
(by keeping it in the hottest portion) and gradually working 
forward, lastly the head. When all is dry the skin should 
be removed from the straw by careful use of some blunt in- 
strument or the finger nail. 
A piece of wire is then taken, a little over twice the length 
of the larva, and bent into the form shown in fig. 10, the free 
ends being slightly incurved. A drop of shellac dissolved 
