He could do so with reasonable assurance that the weevil attacking his species of nut would not occur upon his trees until brought into the locality by artificial means. There is another group of weevils, nearly related to the common plum curculio, the species of which attack immature nuts. In this group the snout is much shorter than in the group just described, and the insects are considerably smaller. There is one species, _Conotrachelus juglandis_, that confines its attacks to the young fruits and shoots of walnuts of the butternut group, another, _Conotrachelus retentus_, that seems to attack exclusively the black walnut fruits from the time they set until they are half grown, still another, _Conotrachelus affinis_, that appears to attack only half-grown hickory nuts. Another species, _Conotrachelus aratus_, feeds abundantly in some localities within the leaf petioles of hickory. At least two other species of the group commonly attack acorns. Those injuring walnuts lay their eggs on the concave side of crescent-shaped punctures which they eat in the husks of the young nuts. The larvae developing from the eggs cause the nuts to drop within a few weeks and the larvae enter the ground to complete their transformation. There is a divided tendency with some of these species to attack the young wood and leaf stems of the introduced species of walnut. Dr. Morris states that he has had young Japanese walnut trees killed by _C. juglandis_ feeding in the grub stage within the branches. He has, however, found that the pest succumbs to an arsenate of lead spray. Species of this group are apt to have alternating periods of increase and decrease and a year of great abundance may be followed by a year of comparative scarcity. This variation is due, at least in part, to the fact that the larvae, as they feed within the tissues of their host plants, often become rather heavily parasitized by certain two-winged and four-winged flies, the parasitized larvae dying before they reach the adult stage. Nature in this way does considerable toward holding the pests in check, but artificial means of control will often need to be considered.