THE SUGAR-CANE MOTH BORER. 61 



The writers were prevented from introducing parasites known to 

 attack the moth borer in Cuba, however, and it seemed worth while 

 to give Ceromasia a trial. A cage isolated from ants was arranged, 

 and in 2 feet of soil at the bottom of this cage a number of cane plants 

 were set. Later nearly 200 stalks of cane containing tunnels of the 

 moth borer and probably many borers were secured and put into the 

 cage, one end of each stalk being pushed into the ground. Mr. Otto 

 H. Swezey, entomologist of the Hawaiian Sugar Planters' Experi- 

 ment Station, in September, 1917, kindly gave directions for the 

 preparation of this cage and caused puparia of Ceromasia collected in 

 Hawaii to be sent to the writers, who placed the adults in the cage as 

 soon as they emerged. Eighty-seven puparia were received, from 

 which 23 flies emerged. About half of the adults were small, but 

 many were of normal size. Mr. Swezey's instructions were followed 

 closely, ants were kept out of the cage, the plants were sprinkled 

 daily, and honey and overripe fruit were provided as food for the 

 flies. 



It was found that the infestation by the moth borer in the cage 

 was far higher than that usually found in the field. The growing 

 plants were so heavily infested that they did not make any appre- 

 ciable growth throughout the remainder of the season. Though pro- 

 vided with possible hosts in such numbers, the parasites did not 

 attack the borer. Some of the cane stalks were cut open at the end 

 of six weeks, the length of a generation of the parasite in Ha- 

 waii, but no evidence was found that they had parasitized any borers, 

 although many live borers were found. More cane was examined 

 later with the same negative result. 



EXPERIMENT WITH A PARASITE FROM CUBA. 



In 1915 the junior author went to Cuba to obtain, if possible, a 

 tachinid parasite of the moth borer which had been reported by 

 Mr. George N. Wolcott. It was found that while the moth borer was 

 present, it was by no means as injurious as in Louisiana, and that 

 the tachinid parasite Euzenilliopsis' diatraeae Townsend evidently 

 had much to do with its comparative control. 



Living puparia of the tachinid parasite were obtained and for- 

 warded to the senior author in New Orleans from time to time dur- 

 ing the summer of 1915. Cages of many kinds were utilized, al- 

 though none of the type which had been found satisfactory in Hawaii 

 with tachinids was used. In every experiment the parasites died 

 without attacking the host larva? provided for them. Finally it was 

 decided to release the adults in the fields at Audubon Park as soon 

 as they emerged from the puparia. Following this action, during 

 the next grinding season one puparium was recovered in a stalk of 

 cane, and an adult of the species introduced from Cuba emerged 

 from it. 



