6 CIRCULAft 3 8 6, XJ. S. DJii'AllTMJiJSrT OF AGRICUL.XUKJ!; 



the cells containing pollen are mostly avoided, although cells con- 

 taining honey may be riddled. It is known, however, that larvae 

 will eat pollen and develop on it. Wax moth larvae sometimes chew 

 off the cappings of the cells containing sealed brood, and, while the 

 bees may repair some of the damage, many cells will be left only 

 partially closed. 



Although larvae can develop on foundation, the mortality of such 

 larvae is high, and the developmental period of those which survive 

 ip much longer than that of normally fed larvae, and the resulting 

 adults are small and almost white. It is almost certain that damage 

 reported by beekeepers in Louisiana as caused by the lesser wax 

 moth {Achroia grisella Fab.) is caused by such poorly fed larvae of 

 Galleria meUoneUa, since no specimens of the true lesser wax moth 

 were observed during the author's studies. When the larvae are 

 forced to exist on the lighter comb and the outer portions of the 

 cells which have been left untouched by the previous broods, the 

 damage done by them, such as the webbing and external feeding, 

 and their later appearance greatly resemble the work and appearance 

 of the lesser wax moth. 



The optimum temperature for the development of the larvae is 

 between 85° and 95° F., about that normally found in a beehive 

 during the active season. At lower temperatures development is 

 slower, but, unless the temperature falls below 60°, no other influence 

 on the larva has been noted. At temperatures of 40° to 45° the 

 larvae seem to become dormant, and no feeding or growth takes 

 place. 



THE PBHPUPA 



Before pupation the full-grown larvae spin a dense, tough, silken 

 cocoon. IJsually this cocoon is firmly attached to the side of the 

 hive, to the frame, or other solid support, but in some cases the 

 cocoons are found in the mass of tunnels and refuse of the wax of 

 the frames or on the bottom of the hive (fig. 3). In many cases a 

 hollow is chewed out of the wood of the hive or frame, and the 

 cocoon is placed in this for added protection. Frames may be found 

 in which holes have been bored completely through the end or top 

 bars, and the cocoon and pupal case will be found inside these 

 holes. This habit of the wax worm is responsible for a considerable 

 part of the damage caused by the insect, since in heavily infested 

 colonies not only the wax but also the frames are destroyed. In such 

 cases particles of the wood borings are incorporated in the cocoon, 

 which is then well disguised. The fully grown larvae migrate to 

 considerable distances before the cocoons are spun, and pupal cases 

 may be found beneath the hive and even on the more protected 

 parts of the hive stand. 



THE PUPA 



Within the cocoon the larva changes to the pupa. The duration 

 of the pupal stage within the cocoon ranges from 8 to 62 days, 

 depending on temperature. As with many other insects, the pupal 

 period allows the wax worm to pass through the fall and winter 

 protected against climatic influence to a large extent. In the South, 

 especially during warm winters, the adults may emerge at any time 

 during the winter. 



