SCIENCE AND INDUSTRY. 
that much fuller knowledge should be obtained. This could probably be achieved 
by requiring the notification of all land infested by prickly pear, with an esti- 
mate of the degree of infestation divided respectively into “ ineradicable prickly 
pear,” “heavily infested with prickly pear,’ “lightly infested with prickly 
pear,” and “scattered infestation.” In the first category would appear infesta- 
tion where the cost of eradication would be far greater than the value of the 
land reclaimed, Heavy infestation would mean that though the cost of destruc- 
tion was considerable, it would still be under the value of the land. Under 
light infestation would be placed. country where the cost of eradication would 
A CACTUS LONGICORN BEETLE— Moneilema crassum—which, in Texas, feeds on the joints 
of cacti, the larva destroying the internal tissues of the attacked plant. (From “'The 
Principal Cactus Insects of the U.S.A.,” Bulletin 113, Bur. Entomol, U.S.D.A., 
1912, plate 1.) 
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