250 Mississippi Valley HoriiGultural Society. 



a])pears early in the season, and does its mischief prinoii>ally in tlie months 

 of April and May, the beetles appearing in June and July. That the eggs 

 arc laid by this beetle in the jireceding year, is rendered highly probable, 

 in whioh case the species hibernates in the eg<r. Paria, on the other hand, 

 certainly pisses the winter as an adult, doubtless layin,:;- its eggs in the spring, 

 and making its chief attack upon the jilants in July, the beetles emerging in 

 the latter part of July and early in August. Scelodonta, again, hibernates in 

 the larval condition, (the root-worms having gained their growth the pre- 

 viou.-< autumn), pupates in the spring and emerges in June. The eggs are 

 probably laid in July, and the larvae make their attack on the plant in Au- 

 gust and September, continuing it possibly through October as well. Cer- 

 tainly by November they have gained their growth, and formed cells in the 

 ground for their hibernation. The beetles of all these species live in part 

 upon the leaves of the strawberry, especially at first, but scatter afterwards 

 elsewhere, feeding upon various kinds of vegetation ; Colaspis especially upon 

 the grape, Paria upon the juniper and crab apple, and Scelodonta upon the 

 evening primrose, and probably upon heads of grass. 



In their larval stiige, all, as far as known, depend strictly upon the roots of 

 strawberries for' food, devouring especially the smaller fibrous roots, but also 

 penetrating and perforating the crowns. An attack in force is extremely 

 destructive, and rapidly kills the plants affected. Often as many as fifteen or 

 tw<'nty larvfe occur in or about the infested stool. This injury is maintained 

 throughout the season, the species attacking the plant successively — Colaspis 

 first, Paria next, and Scelodonta last. 



Finally, in the absence of conclusive experiments on the artificial destruc- 

 tion of these pests it will be worth while only to say that Paris green or Lon- 

 don purple applied to the leaves from June to August, will take efl(3ct upon 

 the mature beetles as they emerge from the earth, and will thus unquestion- 

 ably limit the increase of the larvae ; while it is probable that applications of 

 crude carbolic acid, bi-suljihide of carbon, or similar substances destructive 

 to larval life, may be profitably made in the earth of infested fields, with the. 

 view to killing the larvie in the ground. It is especially likely that this last, 

 or some similar measure, will prove worth while (if hscmI in lime) for the des. 

 truction of tlie larvte when they first make their appearance, in isolated 

 patches in the field. 



Lalx^ratory experiments w^ith both the above mentioned substances, made 

 by punching holes in earth containing the larviu, i)()urim; in a lillle of the 

 insecticide!, and then filling the holes with earth, demonstrated the suscejjti- 

 bility of these root-worms to the vapors of both caritolic acid and bi-suli)hide 

 of carbon. No opportimity has ofi'ered for field experiment. 



If it be desired to destroy the root-worms by plowing up the jilants, the 

 time for this must evidiiilly depend upon the species by whidi ihe field is 

 occujiiiMl; since this measure will be inefTective unless taken wlien either the 

 eggs or the yoimg larvx- are ex])(jsed to it. To kill Ccjlaspis, the jilants must 

 be destroyed immediately si{Uir the fruit is picked ; Paria may be reached in 

 July, and Scelodonta in .\ugust. 



