INSECT NOTES. 843 



moth, Halisidota caryce Harris, and its abundance in Connecticut 

 during the past two years. It was also very abundant in the 

 summer of 1908 and did some damage to various kinds of trees, 

 but in September and October many dead caterpillars were 

 observed adhering to the trunks and branches of trees and some- 

 times on fences and stone walls. These had been killed by a 

 fungus which, according to Dr. Clinton, has been studied and 

 named in manuscript by Professor Roland Thaxter of Harvard 

 University, but the description and name have not yet been pub- 

 lished. From the number of dead caterpillars seen while inspect- 

 ing nurseries about the state, this fungus must be regarded as 

 an important natural enemy of the species. In some cases a 

 dozen of these dead caterpillars would be found on the base of the 

 trunk of a single tree, and there were probably many more on 

 the branches. The appearance of a fungus-killed caterpillar may 

 be seen on Plate LIX b. Other species of caterpillars, notably 

 H. tessellaris and probably Estigmene acraa, were killed in a 

 similar manner by this or some other agency, though only a few 

 of them were found. 



Lead Arsenate vs. Paris Green for Spraying Potatoes. In the 

 experimental field at Mt. Carmel, Doctors Clinton and East of this 

 station have each year grown three or more acres of potatoes. 

 During 1908 they made arrangements with the writer to take 

 charge of the first sprayings to kill the Colorado beetle, before 

 it was time to use Bordeaux mixture. Little damage was done, 

 so the first treatment was given June 22d. On two plats of 

 one acre each on the northwest corner of the field, conditions 

 were practically uniform as regards the plants and their infesta- 

 tion. Here and there throughout, certain hills were badly eaten, 

 though most of the plants had not been injured. The acre plat 

 nearest the road was treated with Paris green, one-half pound 

 in fifty gallons of water, and two pounds of lime added. The plat 

 adjoining this on the east was sprayed the same day with lead 

 arsenate, three pounds in fifty gallons of water. Both poisons 

 were used upon the third acre. A hard shower came the next 

 day. On June 27th, four days after the treatment, the potatoes 

 were examined and the fewest larvae were found on the field 

 sprayed with lead arsenate, while no injury to the plants could 

 be detected. Where Paris green was used, not only were the 



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