6 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



The following program was presented: 



NOTES ON THE HABITS OF WEEVILS. 



(Coleoptera, Rhyncophora .) 



BY W. DWIGHT PIERCE. 



To the student of biologies the study of the weevils furnishes 

 no end of surprises. We find almost every possible variation in 

 insect life-history except those associated with parasitism. Among 

 the weevils are external and internal plant feeders, predators 

 on scale insects and m on woodboring insects, cannibals, inquilines, 

 and myrmecophilous species. They breed in every portion of 

 plants and some of them form galls. We find the eggs laid singly 

 and in cluster, exposed and concealed. Different species have 

 very clever ways of preparing the food for the young such as 

 making elaborate leaf rolls, scraping the surface of fruit to make 

 a scaly covering, puncturing the midrib of a leaf to prevent sap 

 flow and growing fungus upon which the young may feed. The 

 larvae are either external or internal feeders, phytophagous or 

 entomophagous, sometimes even semiaquatic or aquatic. Many 

 prepare silken cocoons. Some cover themselves with excrement. 

 They mine leaves, tunnel stems, breed in buds, flowers, fruit or 

 roots or eat the outer surface of plants. Some pupate in the 

 plants, some on them, and many enter the ground. The devel- 

 opment takes from a few days to several years. 



In the course of the last few years the writer and his associates 

 had occasion to work out the life histories of many species. While 

 these will be written up in full in the future it may be sometime 

 before they can be published and it seems advisable to publish 

 at this time brief notes covering as much of this work as possible 

 so that other workers may have the advantage of them. 



The genus Apion has been divided by European authors 

 into a number of genera of which the characters correspond 

 remarkably with the biology. A preliminary glimpse at the 

 records of our American species indicates that we can coordinate 

 our classification in the same manner. It will be first necessary 

 to learn more about our species. The following records increase 

 materially the knowledge of American Apioninae. 



Apion impunctistriatum Smith breeds in the stems of the 

 composites, Heterotheca subaxillaris and Ambrosia trifido in 

 Texas. 



Apion ellipticum Smith forms a gall in the roots of Chaero- 

 phyllum texanum, an umbelliferous plant. A 17 per cent control 

 by parasitism was found at Dallas, Texas in 1907. 



Apion falli Wagner (pyriforme Smith) breeds in the pods of 



