154 EXPERIMENT STATION RECORD. 



species, with one or more species of CriiUegus as its original food. In addition 

 to tlie apple, it may attack hybrid crab apples, haws {Cratcegus sp.), huckle- 

 berries, and ))lueberries. 



It is shown that its present known distribution approximates in general the 

 limits of the eastern or humid part of the Transition Life Zone; in other words, 

 the so-called Alleghanian Zone. It reaches its greatest abundance and de- 

 structiveness in Maine, in New Hampshire, parts of Vermont, in Massachusetts, 

 parts of Connecticut, and New York, with an additional wide, though scattering, 

 distribution in Ontario, Michigan, and Pennsylvania. It is also present in 

 Canada — in Nova Scotia, New Brunswick, and Quebec. An account given of its 

 occurrence in the United States is based upon correspondence with state and 

 station entomologists. 



Its economic status in New Hampshire is next dealt with at some length in 

 connection with a questionnaire in which 210 replies were received from fruit 

 growers who represented practically all sections of the southern two-thirds of 

 the State. The factors influencing comparative infestation are season of ripen- 

 ing, aroma, and thickness of skin; location is an indirect factor. Of twelve va- 

 rieties of which the most reports relating to infestation were received, six were 

 summer or fall fruit, and of these, five varieties, namely, the Porter, August 

 Sweet, Found Sweet, Hubbardston, and Early Harvest, are notoriously severely 

 attacked. 



Life history studies based upon the work at one or more of three places in 

 the vicinity of Durham are reported. They deal with the dates of emergence 

 of the adult, influence of temperature and moisture on rate of emergence, ovipo- 

 sition, choice of varieties for egg laying, number of egg punctures per apple, 

 period during which eggs are laid, length of the life of the female, dispersion 

 habits of the adults, etc. The studies have failed to give evidence of the occur- 

 rence of a second brood in the State. The emergence of the adults begins the 

 last of June or the first week of July, is at its maximum in the second and third 

 weeks of July, and is practically at an end by the middle of August. Oviposi- 

 tion may begin in less than a week after emergence, commencing the first or 

 second week of July and proceeding until the latter part of September. From 

 five to seven days are passed in the egg stage. The larval stage may be passed 

 in 30 days or less, or may be greatly prolonged. The duration of the pupal 

 stage is widely variable, the species exhibiting both a 1-year and a 2-year life 

 cycle. In the 1-year cycle the pupal stage occupies approximately 300 days. A 

 proportion of the early as well as the late-maturing larvse may requii'e an extra 

 year for the pupal stage. Technical descriptions of the several stages are in- 

 cluded. 



Under control measures the author discusses poison bait spraying, relation 

 of codling moth sprays, and poison trap pans as measures directed against the 

 adults ; control by picking up drops and the use of live stock to keep the drops 

 cleaned up as measures directed against the larvje; and the use of poultry, use 

 of chemicals in the soil, burying pupa; by plowing, compacting the surface soil, 

 and cultivating the soil as measures directed against the pupa;. " Poison bait 

 sprays, in three years' extended trials in New Hampshire, have entirely failed 

 to insure satisfactory protection of fruit from attack by the maggot. With 

 five or more applications the apples often show abundant egg punctures. Even 

 with ten applications the fruit may be worthless. The adults are not materially 

 atti'acted to the bait, as so far devised, and are not poisoned in sufficient num- 

 bers to render the treatment a definite benefit in the absence of other measures 

 of control." " Emergence of adults can not be prevented by burying the pupse 

 by plowing, or by cultivating the soil ; and probably not by compacting the sur- 

 face." 



