SOME INSECTS INJURIOUS TO THE VIOLET, ROSE 

 AND OTHER ORNAMENTAL PLANTS. 



THE GREENHOUSE LEAF-TYEE, 



(Phljctzenia rubigalis Guen. ) 



One of the most troublesome of all known enemies of violets and 

 other ornamental plants when once it obtains foothold in a conserva- 

 tory is the greenhouse leaf-tyer, the larva of a small moth, now known 

 as PJdyctcenia rubigalis Gn., but formerly as P. ferrugalis Hbn. 



Until within recent years only a few instances of injury by this 

 species had come to our knowledge or been brought to public notice. 

 During the past four years, however, its depredations have attracted 

 attention in widely separated localities, and it is evident that this insect 

 has now become established as a pest more than periodically injurious. 

 As such it is entitled to somewhat extended notice. The greenhouse 

 leaf-t} T er, as its name would suggest, is more particularly annoying to 

 ornamental plants grown in greenhouses; but its injuries do not cease 

 here, since the larvae work also in the field — celery, beets, cabbage, and 

 tobacco, among crop plants, being most often affected. 



NATURE OF INJURY. 



The usual manner of work of the larva is upon the underside of a 

 leaf. A fair specimen of larval injury to violets is shown in Plate I, 

 which is reproduced from a photograph. The leaves figured were 

 eaten out in holes on the under surface, leaving the upper epidermis 

 intact, and this is the manner of injury to many other plants. Some 

 plants, however, are eaten entirely through and some are skeletonized. 

 Occasionally larvae, when numerous, feed upon the upper surfaces of 

 the leaves, but this is exceptional. The normal habit of the larva in 

 feeding is to fasten together two contiguous leaves, to curl over the 

 edge of a single leaf upon which it may be feeding, or to spin about 

 itself a thin, filmy web within which to feed. 



In close confinement a few larvae will in a very short time devour 

 and destroy their food plant. In one experiment in rearing this species 

 at this office, larvae completely destroyed a large pot of violets in ten 

 days. 



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