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they proved to be, so far as I could see, identical, and ray opinion was 

 confirmed by referring the specimens to your office. The Apanteles 

 had been most abundant in the gardens of a Mr. Gregory, a gardener 

 near Ames, but about 3 miles from where the Apanteles had been in- 

 troduced, and it seemed almost impossible that they could have become 

 so widely distributed and so abundant in so short a time. I made care- 

 ful inquiries of Mr. Gregory, and found that the parasite had been first 

 observed by his wife in the fall of 1890, but in small numbers, and at 

 the time supposed to be an injurious species, and all that were observed 

 had been destroyed. During the summer just past, however, she had 

 seen the larvae issuing from the caterpillars and rightly appreciated 

 their beneficial nature. They became so abundant in Mr. Gregory's 

 garden that he told me they had entirely destroyed the cabbage worms 

 on his place, and they also multiplied extensively in the cabbage patches 

 on the college farm, so that there will probably be very few of the cab- 

 bage worms another season and even if they appear in some numbers 

 the parasites should be so thoroughly distributed as to be able to keep 

 them entirely in check. 



While this occurrence of the Apanteles by some previous introduction 

 makes it impossible to say with certainty whether any were established 

 as a result of the introduction of last spring (and the probabilities were 

 against a successful issue in this case) there is the strongest proof of the 

 ability of the species to thrive and to successfully reduce the numbers 

 of Pieris rapce. It w ould be of interest to ascertain the source from 

 which they were introduced, but nothing could be learned of any proba- 

 ble introduction direct from any distant point and it seems most likely 

 that the species has simply spread through its own powers of dispersal 

 from other parts of the country where it has been present. It would 

 seem to be a very easy species to distribute from one point to another, 

 but for the Northern States it would seem more easy to introduce in the 

 latter part of the season, as the imagos issue in spring too early to find 

 rapce larvae ready for them to oviposit upon. Mr. Gregory informed me 

 that the parasites were noticed issuing from the pupae as w^ell as from 

 the larvae. 



The Apple Maggot, which reports indicated as common in some sec- 

 tions of the State last year and which it was feared might prove trouble- 

 some to our orchardists, has not been heard from the present season, al- 

 though the apple crop has been a large one. Should it make no further 

 appearance it would seem to strengthen the idea that it does not thrive 

 in this region, perhaps on account of unfavorable soil, a condition that 

 may be viewed with much satisfaction by our fruit-growers. 



