442 I • 22 



and vernal months. But that a goodly proportion of the moths escape 

 all their enemies, our half-ruined apple crops abundantly testify. But 

 though insects which inhabit fruits are in this way protected from many 

 enemies, it is not to be understood that they wholly escape. Two spe- 

 cies of Ichneumon fly are known to attack the larvte of the plum-cur- 

 culio, and Mr. Eiley informs me that he has also bred two species of the 

 same parasitic family from the larvae of the codling-moth. I have also 

 bred one species ; but it is remarkable that from the hundreds of cod- 

 ling moths which I have reared from their larvfe, I have bred but a sin- 

 gle individual of the parasitic Ichneumon, going to show how rarely 

 they find an opportunity to sting these protected larvte, and therefore 

 how little we can expect from them in the way of practically reducing 

 the numbers of fruit-inhabiting larvae. * 



There is another enemy of the codling- worm, of which, we believe, 

 no public notice has been taken. Our attention was first called to it by 

 a commimication from Dr. James Weed, of Muscatine, Iowa. 



On the 25th of July, 1871, I received from Dr. Weed a couple of 

 white, elongate, somewhat depressed larvae, between three and four- 

 tenths of an inch in length, with a brown head and straight mandibles, 

 with two brown spots on each of the three first segments, those on the 

 first being sub- quadrate, and the others round and successively decreas- 

 ing in size, and with a brown horny plate on the end of the last seg- 

 ment, from which pr<2iect backwards a pair of short and slightly in- 

 curved spines. Dr. Weed stated that these were samples of a kind of 

 predaceous worm which were found in considerable numbers devouring 

 the larvsB and pupae of the codling-moth, so that in some cases the 

 pupae under the bands were almost wholly destroyed by them, and that 

 he had seen them, in several instances, with their heads immersed in 

 the body of a pupa. Having had my attention drawn to this insect, I 

 subsequently saw them, from time to time, under the bands upon the 

 trees in my garden, and in one instance saw one of them in the act of 

 eating a codling pupa. These little worms are the larvae of a small, 

 black, oblong and somewhat flattened beetle, belonging to the genus 

 Trogosita. They exactly resemble the figures of the larva of the Eu- 

 ropean Trogosita mauritanica, in Westwood's Introduction, Vol. I., p. 

 142, fig. 21; and also in Curtis' Farm Insects, p. 330, fig. 27. We have 

 two common American species of this genus, the T. castanea and the 

 T. corticalis, of Melsheimer, and I have seen the latter under the same 

 bands with the larvae. 



* In a letter received from Mr. Kiiey, since writing the above, he states that of one of the species 

 ot Ichneumon flies reared by him from codling-worms he has obtained but three specimens in all ; 

 but of the other species a much larger number. From one lot of 162 worms he bred 21 flies. He very 

 plausibly conjectures that in these latter instances the worms were stung after they had left the 

 apple, and probably after they had changed to pups. 



