larvae could possibly serve as transducers 
to transfer radiant energy from the environ- 
ment to the central nervous system of the 
insect. In considering the IR environment, 
not only are the absorption and reflection of 
such frequencies important but also the trans- 
mission of specific wavelengths through vari- 
ous materials. Thus, a leaf surface between 
a moth or a larva and an IR source may serve 
as a filter in one region of the IR spectrum or 
as a window in a different region. For in- 
stance, glass transmits visible radiation but 
blocks many IR as es 
Figures 15, a to i, presents oscilloscope 
recordings of transmission through various 
substances in the 9- w region as follows; a 
represents the total signal from a blackbody 
emitter through a _ silver chloride filter 
(9.08); b, the background laboratory fre- 
quency (9.75); c, the transmission through 
a sheet of yellow tablet paper; d, a corn leaf; 
e, a latex glove; f, a lens paper; g, a paper 
napkin used in rearing; h, a wire screen; and 
i, the wire screen removed at the center line 
of the oscilloscope to show the rise to maxi- 
mum temperature (9.08u ), The reader should 
note that in the 9- uw region about a third of the 
total emission penetrates a corn leaf. Over 
two-thirds is transmitted through the paper 
napkin, which we use as a surface for corn 
earworm oviposition. 
Table 6 (Summer 1962) gives the thickness 
of certain woods that can be permeated by 
IR radiation. Some woods freely transmit 
certain wavelengths and are thus open windows 
to such frequencies. The implications for 
parasites that locate wood-boring larvae are 
obvious. A tremendous amount of work needs 
to be instigated on IR transmission through 
the various materials found in nature. 
Si. 
iis olf 
By 
PT Rae 
Pf 
ga 
Ei mes 
e 

Figure 15,--Transmittance of 8- to 13-y FIR through various materials (see text), 
(a) Blackbody emitter ( A max, 9.08 4 ), (b) background emission (9.75), (c) yellow 
tablet paper, (d) corn leaf, (e) latex glove, (f) lens paper, (g) paper napkin, , (h) wire 
screen (i) wire screen removed at center line to show rise to maximum temperature 
(9.084). 
