48 THE DURATION OF LIFE. [I. 



Biiprcstis sp/rndeiis. A living individual was removed from 

 a desk which had stood in a London counting-house for thirty 

 years ; from the condition of the wood it was evident that the 

 larva had been in it before the desk was made '. 



Blaps mortisaga. One individual lived three months, and 

 two others three 3'ears. 



Blaps fatidica. One individual which was left in a box and 

 forgotten, was found alive when the box was opened six years 

 afterwards. 



Blaps obtitsa. One lived a year and a half in confinement. 



Elcodcs gratidis and E. dentipes. Eight of these beetles from 

 California were kept in confinement and without food for two 

 years by Dr. Gissler, of Brooklyn ; they were then sent to 

 Dr. Hagen, who kept them another year. 



Goliatliiis caciats. One individual lived in a hot-house for 

 five months. 



In addition to these cases, Dr. Ilagen writes to me : 'Among 

 the beetles which live for more than a j^ear, — Blaps, Pasiwachus, 

 (Carabidae) — and among ants, almost thirty per cent, are found 

 with the cuticle worn out and cracked, and the powerful man- 

 dibles so greatly worn down that species were formerly founded 

 upon this point. The mandibles are sometimes worn down to 

 the hj'podermis.' 



From the data before me I am inclined to believe that in 

 certain beetles the normal length of life extends over some 

 years, and this is especially the case with the Blapidae. It 

 seems probable that in these cases another factor is present,— a 

 vita jin'nijna, or apparent death, a sinking of the vital processes 

 to a minimum in consequence of starvation, which we might 

 call the hunger sleep, after the analogy of winter sleep. The 

 winter sleep is usually ascribed to cold alone, and some insects 

 certainly become so torpid that they appear to be dead when 

 the temperature is low. But cold does not affect all insects in 

 this way. Among bees, for example, the activity of the insects 

 diminishes to a marked extent at the beginning of winter, but 

 if the temperature continues to fall, they become active again^ 

 run about, and as the bee-keepers say, ' try to warm themselves 

 by exercise'; by this means they keep some life in them. If 



' * Entomolog. Mag.,* vol. i. p. 527. 1823. 



