3i6 



Journal of Agricultural Research 



Vol. Ill, No. 4 



punctures, developed no flies, and their pulp was in a sound though 

 somewhat shrunken condition after they had been held in the laboratory 

 for one month. 



That there takes place in citrous fruits a very great and pre\'iously 

 unrecorded mortaUty among the eggs and larvae is clearly set forth in the 

 data in Table I. This mortaUty is especially pronounced in grapefruit, 

 lemons, sweet oranges, and Kusaie limes in Hawaii, is less in Hawaiian 

 hmes and sour oranges, and very much less in Chinese oranges. It has 

 been a common belief among many in Hawaii that citrous fruits are too acid 

 to permit thelar\'setoUve in their pulp until ripe, in spite of the contradic- 

 tory evidence that the quite acid Chinese orange is generally infested. 

 The data in Table HI are here given in proof that no citrous fruit, not 

 even the lemon, is too acid for the development of Mediterranean fruit-fly 

 larv'ae. A study of the data shows that there is a high mortality among 

 larvae transferred to citrous fruits. Too much importance, however, 

 should not be placed upon this, as these fruits must be mutilated some- 

 what in the process of transferring the larvae and therefore are more 

 easily attacked by decay fungi, which bring about a condition not espe- 

 cially desirable for the growth of larvae and often positively fatal to their 

 development. The data are of special interest in proving that even 

 first-instar larvte are able to reach maturity in well-grown though green 

 lemons. The percentage of first-instar larvse maturing in green lemons 

 was in several instances even greater than that of larvae maturing in ripe 

 lemons. 



