329 



noticed that our common bean-weevils "die out" when breeding in 

 small bottles or jars with a limited food supply. 



The North American species of the three genera, Tribolium, Echo- 

 cerus, aud Palorus, have been treated by the writer systematically in 

 revisioual form in a paper to be published in the Proceedings of the 

 National Museum, but as the subject of the distribution of these 

 species outside of our own fauual limits has not been discussed, a few 

 remarks on this head will not be out of place. The injurious forms, of 

 which there are five species, are destructive to grain, fiour, and meal, 

 and are popularly known as "flour weevils." 



The three species of Tribolium have been separated in our local col- 

 lections with rather surprising results as regards distribution. 



THbolium confusum Duv. derives its name from the fact that the 

 species has been generally confused with ferruginenm. Prior to the 

 appearance of Duval's description, published in 1868, both species were 

 known under the latter name, and until within the year the same has 

 been the case in America. As a consequence our literature, mostly 

 ti^eating of ferrugineum, may refer to either species. 



At the Columbian Exposition a large series of the genus was gath- 

 ered from many exhibits from nearly all of the warmer countries rep- 

 resented in the Agricultural Department. Of these all but a small lot 

 from Liberia were identified asferrugineum. In the National Museum 

 collection the order was reversed, ferrugineum being represented by 

 only a small series while of confusum there was an unlimited supply. 

 Duval and other writers of his time appear to have known confusum 

 only from the south of France, and in the 1891 edition of the "Cata- 

 logus Coleopterorum Europi^" we find only France, Germany, and Italy 

 as its distribution in Europe. E. A. Fitch and others, however, had 

 previously recorded this insect from England. There are records of 

 "its occurrence in Siberia, Mexico, and Japan, and we may now add 

 Liberia, and Montserrat, West Indies. In the United States there is 

 nndoubted j)roof of its occurrence over nearly the entire country. I 

 have identified specimens from Michigan, New York, Pennsylvania, 

 Massachu.setts, District of Columbia, West Virginia, Kansas, Califor- 

 nia, New Mexico, Arizona, and Dakota. 



Tribolium ferrugineum Fab. — Of this sjiecies I have seen specimens 

 from North Carolina, South Carolina, Georgia, Florida, Louisiana, 

 Texas, Nebraska, Oklahoma, aud California. Although all except our 

 latest foreign records of distribution are unreliable, it is undoubtedly 

 widely <listributed over Europe and Asia, and its recorded occurrence 

 at Panama, Hawaii, Guadeloupe, Madeira, aud the Canary Islands is 

 probably in all cases correct. At the World's Fair it occurred in exhibits 

 from Mexico, Guatemala, Costa Rica, Curasao, Argentine, Brazil, Para- 

 guay, and Siam. Mr. Hubbard also has it from Jamaica, West Indies. 



Tribolium madens Gharp. — It has been repeatedly said of this species 

 that it is found abundantly wherever meal or grain is stored, but it is 



