February, '17] COLLINS: wind and GIPSY MOTH 175 



at various distances from the woodlands. Each screen contained 60 

 square feet of cloth upon which tanglefoot was applied. Daily exami- 

 nations were made of each screen and data also taken on the tempera- 

 ture, directic n and velocity of the wind during the dispersion period. 



The screens were located on the bogs at various distances ranging 

 from 400 to 1,200 feet from woodland infestations. From one screen 

 located 600 feet from infested woodland on the northwest and 900 feet 

 on the west, there were removed 62 small larvae during the season, or 

 slightly more than one to the square foot. A total of 143 small larvae 

 was wind borne onto the six screens, which indicated that an average 

 of about 17,000 were blowing on to the bogs per acre. The infestations 

 around these bogs, to date, are only medium in extent, which indicates 

 what happens on bogs bordered by heavily infested woodlands and 

 what the conditions will be here as the surrounding infestations in- 

 crease. Concerted action is needed to prevent further increase of the 

 gipsy moth in towns where cranberries are the main crop. 



In connection with the wind dispersion experiments of the gipsy 

 moth, da|;a were secured on some other lepidopterous species. June 1, 

 1914, Mr. C. E. Hood removed from the screen at Plum Island, Mass., 

 a living first stage larva of Hemerocampa leucostigma S & A. Between 

 the period the larva was found and the previous examination of the 

 screen, the wind blew from the southwest at a velocity of from four to 

 five miles per hour. The nearest tree growth was some willows, two- 

 thirds of a mile distant, across the salt marsh, and it is evident that the 

 larva came from this source. 



Some other lepidopterous larvae were taken on screens located on 

 the hills of New Hampshire in 1913 and 1914. These screens were 

 located 200 to 500 feet from tree growth. One specimen taken in 

 Hillsborough, N. H., where the nearest trees were fully 500 feet dis- 

 tant, was either Hemerocampa leucostigma S & A or Notolophus antiqua 

 L. The specimen taken on the screen was so badly injured after hav- 

 ing been removed from tanglefoot that a more accurate determination 

 could not be made. Both the above species of larvae are thickly 

 clothed with very long acuminate hairs, but are not provided with 

 hairs bearing swellings or vesicles. It was thought by Wachtl and 

 Kornauth^ that the latter hairs with balloon-shaped swellings made 

 the caterpillars buoyant in the air, but more recent investigations tend 

 to militate against that theory. 



Nine specimens of a species of Noctuidce were also taken on the 

 screens. Thdse larvae are yellowish-white with brown chitinous plates 



1 1893 Wachtl und Kornauth. Beitrage der Kenntniss der Morphologie, Biologie 

 und Pathologie der Nonne {Psilura monacha). In Mittheilungen aus dem forstlichen 

 Versuchsvesen Osterreichs, V. 16, 38 p., 3 pis., 8 figs. 



