272 



MAINE AGRICULTURAL EXPERIMENT STATION. 



1915- 



f rass. One berry furnishes sufficient nourishment for one weevil 

 with little or none to spare. All parts of the fruit are eaten 

 except the outer coat of the seeds, and the berry is left just a 

 shell around a mass of fine brown frass. Where the weevil 

 has burrowed near the surface, the skin often appears discolored. 



The writer has not found it possible to keep one larva under 

 continuous observation for they are unable to enter the unin- 

 jured fruit when once removed, and a green berry when punc- 

 tured dries up very rapidly. Not infrequently larvae may be 

 found which have been crushed by the growth of the berry. 



There are 4 larval instars. The head of the newly hatched 

 weevil measures .095 mm. and the succeeding instars measure 

 approximately .11, .13 and .15 with slight variation, especially 

 in the fourth instar. The ratio is 1.16 and the theoretical meas- 

 urements .110, .1275, and .148 agree very closely with the actual. 

 All measurements were made under a magnification of 20 diam- 

 eters by means of a camera lucida. 



All larvae found in the berries w^ere preserved m alcohol with 

 a record of the date of collection and the date of removal, and 

 their instar determined by head measurements. A part of this 

 data is given below in tabulated form. 



1st 2nd 3rd 4th 



1st 2nd 3rd 4th 



1014 



June 30 



I 





1915- 



June 



21 



I 







July 6 I 



. I 3 



2 





June 



22 



7 







July 7 



I I 







June 



25 



I 







July 9 I 





2 





June 



26 



I 







July 10 



2 



5 





June 

 July 

 July 

 July 

 July 

 July 

 July 

 July 

 July 



30 

 II 

 13 

 17 

 18 

 20 



23 

 24 



29 





3 



I 

 I 



I 

 I 



4 

 6 



3 

 3 



I 

 I 



3 



I 



Very few first instar larvae are to be found after the last of 

 June. Second instar larvae occur mostly in early July before 

 the seventh of that month. Third instar larvae were found on 

 quite scattered dates but mostly between July 6 and 11. Fourtli 

 instar larvae are occasionally met with as early as July 6 but 



