Februarj^, '17 



COLLINS: WIND AND GIPSY MOTH 



173 



difficult to find small objects upon it. It was made the same dimen- 

 sions as the old one; namely, 75 feet long with wire 6 feet wide, totaling 

 450 square feet. Another type of screen was also used at Province- 

 town, which consisted of white cotton cloth three feet wide tacked to 

 sides and ends of a small building located near the shore. The top 

 selvage of the cloth was eight feet from the ground and contained 162 

 square feet to which tanglefoot was applied. While there were no 

 caterpillars taken on the cloth screen in 1916 at Provincetown, similar 

 cloth screens at Sahsbury Beach, Mass., and Isles of Shoals, N. H., 

 in 1913 and 1914 gave similar results to the wire screens. 



Two men were stationed at Provincetown in 1916 and were able to 

 make from 5 to 8| examinations daily, thus keeping the screen clear 

 at all times in case of sudden shifts of the wind. The details of the 

 daily catches are given in the following table for 1915 and 1916: 



Table Showing Number op P. dixpar Larv^ caught on Screen, Provincetown, Mass., 1915 and 1916, with 

 Direction and Distance prom which thet came 



Grand Total for 1915—128 laryae 

 Grand Total for 1916— 27 larvae 



From the foregoing table it will be noted that 23 larvae out of a 

 total of 128 were borne by winds from the westward and south in 1915 

 and 19 out of a total of 27 in 1916 from the same directions. The 



