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a species very common in mushroom houses, and that it was particu- 
larly destructive to the bricks of spawn. The first brood of the insect 
breeds in these bricks and in the compost in which the mushrooms are 
grown, and the second and later broods take the mushrooms thems elves. 
So serious were the attacks of this fly that only one crop, the first, can 
be successfully grown, the later crops being destroyed by the Sciara. 
The insect breeds in any decaying vegetable material, and the species 
had not been determined. 
In reply to a question by Mr. Hopkins, Mr. Smith stated that both 
sexes are winged in the case of his species. 
In reply to a question by Mr. Smith, Mr. Hopkins stated that he did 
not mean to assert that all the scab was caused by the Mycetophilid, but 
that it caused one kind of scab. Mr. Smith added that there were 
plenty of scabby potatoes in some fields in New Jersey, but though, 
after hearing of Mr. Hopkins's discovery, lie had examined a great 
many, he had never found an insect associated with it. 
The interrelations of Cerambycid larvae and the woodpecker, and the 
nature of the injury produced by the bird in its attacks upon the larvae, 
were discussed by Mr. Hopkins in answer to questions. Mr. Hopkins's 
paper was accompanied by the exhibition of many specimens of wood, 
showing the markings and work of the insects and birds described. 
Dr. Lintner, after expressing his very great interest in the paper, 
said that the assertion that the Mycetophilidae never attack healthy 
vegetation was somewhat erroneous, as, in the case of the mushrooms, 
they certainly did, and hence the difficulty, or impossibility, of grow- 
ing this crop late in the season. He said also that the case of Aphidid 
parasitism mentioned contradicted Mr. Smith's stand in the matter of 
parasites, and he thought Mr. Smith might be more nearly right if he 
limited his conclusions to field insects; for certainly, in the case of 
indoor insects, parasites are frequently, as in the present instance, of 
exceptional and undoubted value. He asked also if the larvae of the 
clover-leaf weevil, when affected by fungus, are not white in appear- 
ance. 
Mr. Smith replied that the diseased larvae are first gray and become 
black as they shrivel and dry up. 
With reference to the twenty-seven-year life-period for the chestnut 
timber worm, Mr. Lintner expressed himself as regretting any possible 
competitor with the seventeen-year Cicada for the place of the longest- 
lived insect, because we have been so long in the habit of ascribing to 
this interesting species the longest period of insect development. He 
suggested that the Lymexylon case is very likely analogous to many 
others on record, of mere arrested development, in which the larva, 
removed from normal conditions, sometimes remains for years without 
transforming to the adult, as in the case of wood-boring insects emerg- 
ing from furniture. 
Mr. Hopkins suggested the deposit of eggs year after year in the 
