TRIBOLIUM FERRUOINEUM. 1 37 



were they that the amount of the flour that could be lifted upon the 

 ])oint of the large blade of a pocket-knife would contain one or more 

 of the beetles. With the lid of a tin box, an inch and a half in diameter, 

 drawn upward three or four times for four or five inches upon 

 the sides of the bag holding the flour, about five hundred of 

 the beetles were taken. A closer examination of the flour 

 disclosed a few pupae and a large number of the larvae. The 

 yK^_^ latter, rei)resented at b in the figure, were perhaps one-tenth as 

 \j numerous as the perfect insect, and were of greatly varying 

 sizes, from apparently full-grown to those about one-twentieth 

 as large. They were quite rapid in their movements, and 

 could hardly be taken from the flour, from the facility they 

 Fir..3^t.-TRi- displayed in burying themselves and eluding capture. The 



BOI.IUiM FERRU- r J JO O JT 



t'loTiriarvafci beetles were far more active in the evening by gas-light, when 

 au'^iniarglrt?" they would comc to the surface of the flour in the glass vessel 



(After *Vest- 



wooii.) in which they were confined, where for some reason, a marked 



tendency was shown to collect in clusters, clambering over the backs of 

 one another for the purpose. During the several days that they were 

 under my observation, not a single individual was seen to take wing for 

 flight, or to climb up the outwardly sloping side of the glass vessel. 



Heat Recommended for Killing it. 

 Answer was returned the Messrs. Durant, of the name of the insect, 

 its general distribution over the world through commerce, its known 

 habits in Europe as a grain and flour pest, the limited knowledge of it 

 in this country, and recommending an exposure to heat as the best 

 known method of destroying it when infesting grain in bulk or in 

 flour. A moderate degree of heat — from 120° to 130° Fahr., con- 

 tinued for a few hours, would in all probability suffice to kill all of the 

 eggs, the larvae and the pupae in the material submitted, while a higher 

 temperature — perhaps 150° or more — would be needed for the beetles. 



A Well-known Grain Pest in Europe. 



This specie* has long been known to infest meal, grain and various 

 vegetable stores in Europe, and it is somewhat singular that it has not 

 been brought to popular notice as a pest in this country. I am not aware 

 that any of our entomologists have written of its depredations upon grain 

 products. 



Observed as a Museum Pest. 



Dr. Hagen has written of injury done by it to the collection of in- 

 sects of the Museum of Comi)arative Zoology at Cambridge.* After 



* Museum Pests observed in the Entomological Collection at Cambridge. — /Voc. Most. 60c. 

 ^^at. Bist., Oct. 23, 1878, xx, p. 56-62. 

 18 



