94 DEPARTMENT BULLETIN 1267, U.S. DEPT. OF AGRICULTURE 
The beetles also feed upon the common rush (/uwncus effusus). 
The culms of this plant form a dense tuft and are extremely tough 
and dry, except at the base, where they are somewhat tender. The 
beetles attack and cut them off at that point. Owing to the crowded 
condition of the culms at the base of the plant, it was not possible to 
detect the beetles at work, but they were found lying motionless in 
such situations and beside the broken and shredded culms. Tufts of 
the rush, from which all imperfect culms had been carefully removed, 
were transplanted to a cage containing the beetles and, when ex- 
amined several days later, were found to have a considerable number 
of their culms broken off and shredded in the same manner as those 
observed in the field. It would appear, however, that the beetles 
prefer the Paspalum grasses to the rush. 
Bermuda grass (Capriola dactylon) also is probably eaten by the 
beetles, thgugh very much less readily than Paspalum. This grass 
occurs practically everywhere throughout the entire coastal section 
of Virginia and is especially characteristic of the better cultivated 
areas. It abounds in many situations in which Paspalum is scarce 
or lacking. Indeed, it would seem that the chief danger of Huetheola 
rugiceps perpetuating itself in farming districts and other places 
outside its typical habitat hes in the universal presence of this grass 
and the apparent ability of the pest to utilize it as food when no 
other is available. One would imagine that the hard and wiry stolons 
of Bermuda grass would scarcely prove very attractive; nevertheless 
the junior writer has repeatedly found them torn and frayed in the 
manner characteristic of injury by this species. Similar injury has 
also been caused by planting the stolons in a cage containing the 
beetles. 
Corn is attacked by the beetles only in the spring and early sum- 
mer when it is young. Later in the season the stalks become too 
hard for them to penetrate. The plants may be attacked as soon as 
ihey appear above ground, and are not safe from serious injury until 
they are fully waist high. The beetles are particularly fond of the 
apical growing point of the stalk, the so-called “ heart,” which is the 
most vital and important part of the plant. In the early stages of 
growth of the corn plant this structure forms a minute conical bud, 
situated below the surface of the ground in the center of the stalk. 
To reach this part the beetle bores into the stalk at any point between 
the surface of the ground and the point of attachment of the roots, 
making a large, ragged opening (Pl. I, B). The work of the beetle 
is indicated above ground by wilting of the inner set of leaves, the 
outer ones retaining their rigidity for a considerable period after the 
other leaves have died. , 
In a somewhat later stage of growth, after the stalk proper has 
begun to elongate and has carried the terminal bud well above 
ground level, the injury done by the beetle boring into the stalk is 
usually less severe, only a more or less extensive part of the pith at 
this time being destroyed, the more vital growing part being out of 
reach of the beetles. At this time the stalk is also considerably 
thicker than before, and a beetle may finish feeding before it has 
destroyed enough of the vascular supply of the plant to interfere 
seriously with its functions. 
The chief danger to larger corn plants is naturally in the weaken- 
ing of the stalk, which may result in its being blown over or broken 
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