32 Director's Report of the 



in solution and in part in suspension or colloidal solution; and (3) 

 fat and casein are wholly in suspension or colloidal solution. 



ENTOMOLOGICAL DEPARTMENT. 



The cranberry toad-bug.— Bulletin No. 377 contains an account of 

 an investigation to determine the cause of a peculiar dying of the 

 new growth of cranberry vines. Previous to this study the trouble 

 was commonly ascribed to diseases known as " cranberry scald ' : 

 and " cranberry rot." At the initiation of the work it was soon 

 discovered that the causal agent was not a fungus but an insect 

 ( PhyUoscelis atra Germ.) of the family of Fulgoridae. The cranberry 

 appears to be its sole host plant. If the insect attacks the new 

 growth both branch and fruit are killed, but if it feeds on the old 

 wood the berries and branches beyond the feeding point are shriveled 

 and dwarfed. As a result of this injury the yield from certain 

 varieties has been reduced to one-half or one-fourth of a normal 



crop. 



There is but one brood of the insects during the year. The egg 

 is elongate-oval in shape, with a short stalk at one end. The egg- 

 laying period extends from September 1 to the middle of October. 

 Hatching begins on June 25 to 30 of the following summer, and a few 

 may not hatch until early in August. Nymphs usually group to- 

 gether to feed, and may live a long time on the same branch if not 

 disturbed. The insect has five nymphal instars. The first adults 

 appear about the first of August, the males maturing first. 



The habits of the insect suggest two methods for the prevention 

 of injuries: Flooding and spraying, which are discuss3d with con- 

 siderable detail on the concluding pages of the bulletin^ 



The cabbage maggot.— The third contribution by this Station to 

 the knowledge of this destructive pest is made in Bulletin No. 382, 

 and deals especially with the activities of the maggot in relation to 

 the growing of early cabbage. 



Of the insecticides that are employed to destroy maggots about 

 the roots of the plants, carbolic-acid emulsion has generally been 

 regarded as the most efficient. Tests with the emulsion at recom- 

 mended strengths have demonstrated that it will prevent the hatching 

 of the eggs and is fatal to the younger stages of the larvae. It may, 

 however, cause injury to young seedlings and is not a safe remedy 

 for the treatment of plants recently set in the field. 



