hellebore or arsenical poisons to the vines in July; but' if, on the 

 other hand, the spring brood is the only one, it must be combatted, 

 if at all, while the fruit is on the vines, when no poisonous appli- 

 cation would be permissible. To determine this point for Central 

 Illinois, careful observations were made throughout the season, and 

 a large number of individuals were reared. 



On the 12th May, in Normal, McLean County, newly hatched 

 larvae of this species, were observed upon strawberry leaves, and 

 numerous eggs with the partially developed larvae within them. 

 These eggs, some of which were kept for identification until the 

 larvae emerged, were not placed in the petiole, as observed by Kiley, 

 but were thrust beneath the epidermis on the upper side of the leaf, 

 a crescentic slit having first been made by the ovipositor of the 

 female. Attempts were made to carry these newly hatched larvae 

 through their transformations, and a few of them survived until 

 June 5, at which date they were about half grown. Several young 

 Pentatomidae, apparently Euschistus, appeared in the cage at this 

 time, and to their predaceous habit the disappearance of the larvae 

 was attributed. 



On the 13th of June, strawberry slugs of this brood were found 

 upon the leaves in the field, and on the 21st about 150 specimens 

 were collected and placed in a breeding cage. These were fully 

 grown, and began at once to enter the earth, nearly all having 

 disappeared by June 24. On the 19th of July, those in the earth 

 were examined, and found much shortened up for pupation but not 

 yet transformed. At this time strawberry fields where they had 

 been previously abundant, averaging as many as two or three to 

 each leaf, were swept carefully and extensively with an insect net, 

 but not a single strawberry slug was found. 



On the 1st September, the larvae in the earth were examined but 

 found still untransformed, most of them enclosed in small cocoons. 

 On November 24, these conditions were practically unchanged ; one 

 of the larvae was dead, although yet fresh, but the others examined 

 were living and in perfect condition. 



[Delay of publication permits me to add that the above saw-flies 

 were emerging May 14, 1885, from the lot secured for breeding June 

 21, of the year before.] 



The above experiment shows conclusively that in the latitude of 

 Central Illinois, and during ordinary years, the strawberry slug or 

 false worm has but a single brood, and that this is matured before 

 the strawberry harvest is completed, a fact which so modifies the 

 possibilities of effective attack upon the species that we are practi- 

 cally limited to the application of pyrethrum or other harmless in- 

 secticides for the purpose of destroying the larvae, and to the use of 

 the insect net for the collection of the adult flies as they appear 

 upon the vines in May for the deposit of their eggs, and later for 

 the capture of the larvae. These last are detached from the leaves 

 at a touch, and I doubt not may be collected without great trouble 

 or expense by sweeping with an insect net. From this they could 

 be shaken at intervals into a bucket of water covered with a film 

 of kerosene. 



