70 



At intervals the head is slowly and regularly rolled from side to 

 side as if to pry apart the severed tissue, and when the soft in- 

 terior substance of the plant is penetrated a pause is made to en- 

 able the insect to devour the part thus brought within reach of 

 its jaws. By moving forward and backward and twisting to the 

 right and left, the beetle will often hollow out a cavity beneath 

 the surface much larger than the superficial injury would indicate. 

 Ochreiis (and possibly other species also) elongates the original 

 slit by pulling the head strongly backward with the compressed' 

 beak inserted, thus using the latter to split the stem as a boy- 

 uses his knife to split a stick. In this w^ay a slit an inch long 

 may be made in the stalk of corn or head of cane, beneath which 

 the softer parts will be completely eaten out. Our imprisoned 

 beetles, confined with rapidly growing corn, left the lower part of 

 the stalk, as it hardened, and fed at the tip of the plant, or 

 searched out the forming ear, penetrated the husk, and gouged out 

 the substance of the soft cob. The intestines of these beetles were 

 well filled with the solid tissue of the plant, but I saw no evidence 

 that they also suck the sap, although it is not, perhaps, im- 

 possible.* 



The effect on the corn plant of such injuries as the above varies 

 according to the size of the species and the number of the beetles. 

 A small species may do little more than to leave a trace of its 

 visit in the form of a series or two of oblong parallel holes across one 

 or more of the leaves, each row resulting from a single thrust of the 

 beak when the leaves were closely rolled together around the stem 

 of the young plant; but the larger species, especially if several 

 individuals attack the same plant, may completely kill the corn or 

 grass, or so rag and deform the young leaves that no ear is ma- 

 tured. 



In Ford county, near Piper City, where the first crops were 

 being raised after the draining of the swamps, I found, late in 

 June, several fields which w^ere finally being plowed up after two 

 or three times replanting; and even the millet sown after corn 

 was attacked, in some places not more than twenty per cent, of a 

 yield maturing. The perforation of so small a stem by so large a 

 beetle cut the plant off within the sheath and killed it outright. 

 Fox-tail grass (Setaria) was injured in the same manner. 



S. scojyariiis is included among the probable enemies to corn 

 on the strength of an observation made by an assistant, Mr. H. 

 Garman, who found this beetle under ground, at the base of a 

 stalk of corn in Logan county, June 16, 1885. 



S. placulus was repeatedly taken from stalks of corn, just be- 

 neath the surface of the ground, by another assistant, Mr. John 

 Marten, July 7, 1888, and was also sent to me by Mr. Joseph 

 Carter, from liaidcin, Illinois, with tln^ following letter, dntod 

 March 31, 1887: 



♦See Rep. U. S. Ent., 1882, p. 189; and Rep. St. Ent. N. Y., 1882, p. 261. 



