. Annual report of the North Carolina Agricultural Experiment Station . d for the most one finds a pupal cell where the tap-root has been entirelyeaten away; then the pupal cell may be lined with fragments of thewell masticated tap-root. But so far as our observations go, the larvaedo not move material very far with which to make the lining of theirpupal cells, but take whatever comes first to hand, be it either frag-ments of stalk or roots or particles of soil. EFFECTS OF MOISTURE UPON THE FTJFJE The pupae seem to be little affected by moisture. They can bedrowned by complet
. Annual report of the North Carolina Agricultural Experiment Station . d for the most one finds a pupal cell where the tap-root has been entirelyeaten away; then the pupal cell may be lined with fragments of thewell masticated tap-root. But so far as our observations go, the larvaedo not move material very far with which to make the lining of theirpupal cells, but take whatever comes first to hand, be it either frag-ments of stalk or roots or particles of soil. EFFECTS OF MOISTURE UPON THE FTJFJE The pupae seem to be little affected by moisture. They can bedrowned by complete immersion in water, but anything much short ofcomplete immersion seems to have little effect upon them. Neither does The Bulletin 81 the amount of moisture seem to have much effect upon the durationof the pupal stage. Pupae kept in tight tin boxes with the air morethan saturated with water emerged on the average in the same timeas pupae which were exposed to the dry air of an average room or thoseexposed to the average humidity out of doors in a screened Figure 53. Pupal cells formed of corn fiber for protection of pupa; emply pupal cell on leftwas formed in the soil just beneath corn stalk in which the larva completed its cell shown in corn stalk was in natural position at lower end of feeding cavity. 82 The Bulletin MORTALITY OF THE PUPA ]NTot as extensive figures have been kept on the mortality of the pupaeas upon the mortality of the larvae. During 1915 147 pupae wereobserved; from this number 110 adults were secured, giving a totalmortality of slightly more than 18 per cent. Whether this is com-parable to conditions as they exist in the field has not been made during the course of this project would lead one tobelieve, however, that this figure is somewhat high. The pupae usedin this experiment were not often disturbed, and frequently the stalksof corn became moldy or decay set in before they were observed th
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