Results and Discussion 



In some cases very small numbers of newly hatched larvae were reared 

 because of the lack of eggs (table l). The large amounts of media con- 

 sumed by some of the cerambycids in the later instars, and necessity of 

 transferring some larvae several times, prevented rearing more than a 

 few larvae of each species. It is noteworthy, however, that survival was 

 excellent, especially for the cerambycid species. The very small and easily 

 injured nature of scolytid larvae probably accounted for their lower sur- 

 vival figures. In all cases the adults that emerged from the media were 

 normal in physical appearances and capable of flight. The M. rohiniae 

 adults reared on medium B were slightly smaller than the average field- 

 collected beetle, but were otherwise physically normal. 



The scolytid adults produced normal egg galleries and offspring when 

 confined with bolts of wood of their host trees. However, only two species 

 of cerambycids, X. colonus and M. rohiniae, laid viable eggs. The cause 

 of infertility of some of the cerambycids was not investigated, but the 

 medium-reared females of M. caryae produced many viable eggs when 

 mated with field-collected males, which suggests that the males of M. 

 caryae reared on the artificial medium were sterile. Three generations of 

 M. rohiniae were reared on medium B without any apparent decline in the 

 vigor of the beetles. 



To sum up: Many species of wood-boring insects can be reared arti- 

 ficially with good survival. Species with life cycles of up to 2 years in nature 

 can be reared on the media in less than 1 year. Although the artificially 

 reared adults appear physically normal, the infertility of many of the 

 species must be investigated before continuous rearing can be successful. 



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