THE MAMMAL NEST BEETLES. 



271 



coarsely punctured than thorax, the punctures not distant one from an- 

 other more than their own diameter. Length 3-i mm. 



Lake, Marshall, Starke, Kosciusko and Steuben counties; fre- 

 quent. May 20-October 26. 



Family VII. LEPTINID^. 



JIammal Nest Beetles. 



This family is represented in Indiana by a single small, flat 

 beetle, having the antennae slender and 11-jointed; eyes entirely 

 wanting ; thorax with apex truncate, base covering the base of elytra 

 and broadly emarginate, without distinct side pieces beneath; scu- 

 tellum distinct ; elytra rounded at tip, covering the abdomen ; front 

 coxae small, globular, not separated by the prosternum; hind coxse 

 narrow, transverse, meeting at middle; legs short, tibi» flattened, 

 tarsi 5- jointed. 



But two species of the family are known 

 from North America. One inhabits the 

 Hudson Bay region; the other is common 

 to both Europe and America and lives with 

 small rodents and insectivora, such as mice, 

 moles, shrews, etc., and also in the nests of 

 bumble-bees. If the nest of a mouse or 

 shrew be carefully removed from beneath 

 a log or other shelter and shaken over a 

 paper, a number of these little beetles will 

 probably be seen scampering away as fast 

 as their legs will carry them. Chas. Dury, 

 of Cincinnati, took 90 specimens of the 

 beetle from one nest and many others es- 

 caped before he could gather them in. As to whether they are para- 

 sites or guests of their hosts is still a mooted question, but Dury 

 states, and my observation bears out his supposition, that he 

 thinks them "only guests of the animals, as I have found them in 

 nests that have long since been deserted. " It is possible that they 

 may live upon the eggs and young of the mites, fleas and other 

 forms of life found associated with them in the nests. It is thought 

 by some that their original home was in the nests of bumble-bees, 

 where they fed upon honey and pollen, and that they merely make 

 use of the mice and shrews as a means of getting from one nest of 

 a bumble-bee to another. 

 [18—23402] 



Fig. 133. |Liiie''shows'natural8ize. 

 (After Sharp.) 



