42 DRAGONFLIES OF NORTH AMERICA 
creature should be bagged with its own cast skin and kept alive to 
color and harden, The two should then be pinned or papered 
together. 
Only the early-rising entomologist may avail himself of such easy 
picking, but there is another way, sometimes very successful and 
almost as easy, and more congenial to sleepy-heads—a way in which 
the dragontles may be induced to cage themselves, cast skins and all, 
At the height of the season of transformation, 
every dragontly collector has seen some bed of 
water weeds teeming with dragonfly and damselfly 
nymphs with only here and there a stem projecting 
above the water surface, ard every emergent stem 
piled high with cast skins. When the nymphs are 
all moving towards these vantage points for trans- 
formation, if the projecting stems be all cut off 
below the surface and removed, then they will go 
to any other projecting thing that offers, If a stick 
be thrust in the bottom, they will climb up the 
projecting end of that. And if a trap like the one 
shown in figure 22 be placed on the top of the stick, 
they will enter it on transformation and there 
await the arrival of the collector, 
This cage is merely the pillow cage described 
above, with one end left open. The lower end, 
instead of being closed is slit lengthwise in half a 
dozen segments an inch or more deep and the seg- 
nients are bent inward horizontally to form a shelf 
around the lower border. This shelf is to keep a 
fluttering imago from falling out after transfor- 
Automatic mation, If it falls, it will alight on this shelf and 
st ih climb up again. Between the inner edge of the shelf 
and the stick there must be left enough room for the ascending nymph 
to climb into the trap. The wire brace from stick to cage is to prevent 
dislodgement of the latter by wind. The upward inclination at the 
middle avoids interference with the ascent of the nymphs. A pin in the 
top end of the stick keeps the top of the cage in position. Such a cage 
was used very successfully by the senior author at Laguna Beach, 
California, 

Fig. 22. 
